How to clean and get ready for painting

Q. We had some scaffolding up for an extended period (three months) and where it was resting on the deck it has caused some discolouration/staining and we are wondering how this can be removed/rectified. Can you please give some advice on any options we may have?

A. As a starting point I would treat the discolouration with Resene Moss & Mould Killer, as I believe the black staining to be mould, followed by a washdown of the entire deck with Resene Timber and Deck Wash. Hopefully this will even the colour out.

August 2023

Q. I need to do some exterior house prep. There is mould involved, and I was wondering what order you use a killer in terms of washing, scraping, mould killing, sanding?

A. Treat areas of moss/mould infestation with Resene Moss & Mould Killer diluted and used to label/data sheet instructions. For heavy infestations more applications may be needed.

Scrub down using Paint Prep and Housewash diluted and used to instructions. Rinse clean or hose down with copious amounts of fresh water ensuring all wash solution and surface chalk residues are removed.

Then all paint that is flaking or unsound must be prepared by sanding back to a sound feathered edge.

June 2022

Q. Could you please confirm if your Resene Paint Prep and Housewash product is OK for runoff onto sealed exposed concrete?

A. The wash solution will not react/damage the concrete. However, do not allow the wash solution to dry out on any surface, this includes aluminium joinery and window glass. Rinse clean or hose down with copious amounts of fresh water ensuring all wash solution and surface chalk residues are removed. Do not allow runoff to enter waste water drains.

April 2022

Q. I want a safer more natural paint stripper if possible as I want to strip paint off a baby’s cot that has been painted green.

A. We have a water based, biodegradable, low odour, Neutral Ph option for you. It’s called Sea to Sky coating remover. It is applied as a thick gel, and left in the shade away from the sun or excess heat and after a few hours the coating will have reacted and you can scrape the coating and the paint layer off. The gel encapsulates the paint and stops small particles flying off.

February 2022

Q. I am preparing my weatherboards for re-staining. I have applied Resene Moss & Mould Killer as it’s the southern side of the house and there were some visible areas of mould. To be on the safe side, I have applied the product to the whole area and left overnight. I was also advised at my local Resene ColorShop to apply the Deck and Deck Wash prior to staining.

Is it necessary to wash off the dried Resene Moss & Mould Killer residue first, or can I just go ahead and brush on the Resene Timber and Deck Wash?

A. The Resene Moss & Mould Killer wash solution must be washed off before treating with Resene Timber and Deck Wash.

If there is still black residue remaining, then this can be a sign of mould that has not been dealt to by the first application. If the visible mould and mould spores are not killed/bleached they may re grow, while the stain has active mouldicide this is inhibiting but cannot kill mould. Suggest that you try on an area applying a 1:1 dilution of Resene Moss & Mould Killer, note this dilution will give a concentrated bleach solution, so care in mixing and use is required. Check if there is a quick bleach of the black colour, if there is then this indicates the requirement for additional treatment of the areas showing residual black ness.

Extra rinsing with water will be necessary to remove the wash concentrated solution. The Resene Timber and Deck Wash treatment is twofold, a cleaner (dirt/dust chalk) but also to open up the timber to facilitate stain penetration.

Sanding may remove the black material but sanding will not remove mould spores hence the need for the Resene Moss & Mould Killer steps.

Sanding is normally required for areas showing severe greying due to weathering or if the existing stain is a film forming stain, a full sand to remove the existing stain is required before applying a Resene stain.

July 2021

Q. Not sure if you can help but we’ve got some fading on our external boards and over time some staff have tried to spot clean with a chemical and left these marks. Do you know of a product or resurfacer to restore these panels so they don’t look so faded?

A. The issue is more than likely removal of surface chalking from the paint finish. Surface chalking is due to breakdown of the paint upon weathering. The only way to achieve a uniform finish would be to repaint after a thorough scrub down using Resene Paint Prep and Housewash diluted and used to label directions. Rinse clean or hose down with fresh water ensuring all salts are also removed.

February 2021

Q. Can you please advise how to wash walls so that they don't show marks from the damp cloth when they are dry?

A. The tide mark effect is due to the presence of surfactants on the surface, these are normally bound up in the dry paint film but under certain curing conditions, they can rise to the surface. Wipe down the whole wall using warm water and Resene Interior Paintwork Cleaner.

Q. We have an outdoor area next to the house with a wood fired pizza oven, the house and pergola is currently painted with a light coffee coloured semi-gloss acrylic. Unfortunately the smoke and soot from the fire has settled onto the paint and stained it. Is there any special paint or coating we can use in this area to make cleaning easy, without having to remove or recoat the painted surfaces?

A. Sorry but no, however you could try cleaning down using Resene Heavy Duty Paint Prep and Oil Remover diluted and used to label instructions to see if that will help.

Q. What is the cleaning advice for Resene Qristal ClearFloor 2K? My wife currently uses water with a dash of meths on older polyurethane floors, but is this suitable for Resene Qristal ClearFloor 2K? What would you advise?

A. Resene does not have dedicated cleaner for coating. The technical recommendation is to use a microfibre cleaning mop and a dedicated wood cleaner. The key is to use a cleaner that does not leave a residue.

Q. Two years ago we had our apartments repainted with Resene X-200 by professional painters. We now want to wash the building for the first time since painting. The contractor is using a Resene wash product. How does washing the building affect the paint and does it reduce the warranty in any way?

A. Washing down with Resene Paint Prep and Housewash diluted and used to label directions will have no effect on the Resene X-200 other than to remove surface contamination.

Q. I have had advice that if the paint is sound, then I just need to wash the house with Resene Paint Prep and Housewash, apply Resene Quick Dry and then two coats of paint. Is this only for the weatherboards? Will I need to sand windows even if the base is sound?

A. Yes this is what we recommend for weatherboards.

It is always a good idea to sand an existing window paint, to profile for recoating. Dust off then apply a coat of Resene Quick Dry and then two coats of waterborne enamel colour (use the Resene CoolColour™ version of the topcoat colour where dark colours are being used).

Q. I usually buy Resene paint but unfortunately I recently bought a different brand of ceiling paint from a big box store. Several days after applying the paint to the plasterboard ceilings a bad smell developed. I have since spoken to the relevant paint representative who informed me that the smell is caused by the paint being contaminated with bacteria during production. He said to fix it I would need to apply 2 coats of pigmented sealer followed by 2 topcoats. He offered to supply the materials free of charge, although I am not keen to use any more of their paint.

Would this actually fix the problem or only mask the smell for a period of time and would the bacteria continue to grow under the paint and eventually lead to an even bigger problem?

I know this is not a Resene problem but would appreciate your advice on this matter.

A. It is my opinion that the recommended fix would not guarantee resolution of the odour issue. Suggest that prior to repainting that the existing ceiling paint is wiped down with a mould killer such as Resene Moss & Mould Killer diluted to label instructions then apply the sealer etc. You may find that application of the Resene Moss & Mould Killer will remove a proportion of the ceiling paint as some ceiling paints are easily dissolved with water and wiping.

Q. I need to remove lichen off a Colorsteel® roof. I have started doing this using a plastic scraper; do you have a product that will kill the lichen?

A. Spray on Resene Deep Clean, diluted and used to label instructions. Apply on a dull day when no rainfall is expected for at least 12 hours. If the lichen infestation is heavy, spray and then leave for 30 minutes then spray again. Leave, and over time the dead lichen will detach upon weathering. This will take at least a month to start, if you want to after a month, scrub lichen infected areas with a stiff nylon brush to remove dead material.

Q. Our house is clad with Rockcote. Lichen is growing on flat capping around the deck wall etc. Can you advise what product to use, to kill it so it can be removed?

A. Treat using Resene Deep Clean diluted and used to label instructions. Apply on an overcast day and ideally when there is no chance of rain for 12 hours, for areas of heavy infestation apply a coat and then re-wet these areas an hour later. The lichen kill is not immediate but will occur over a month and then the dead lichen will either erode off with rain, or can be scrubbed to remove using a stiff nylon broom.

Lichen growth rates and infestation is micro climate determined, if there is a the potential for growth treatment every 6 months (beginning of autumn and spring) is recommended to achieve continued control.

Q. What can we use to clean the paintwork in our house? At present we use water and sugar soap, but wondered if there is anything else you would recommend?

A. For interior paintwork we recommend Resene Interior Paintwork Cleaner. For exterior paintwork we recommend Resene Paint Prep and Housewash.

Q. We have a late '80s passive solar home with a central concrete block feature wall, which acts as a heat sink. This concrete wall has been left natural but over the years it has become grubby, with some oil stains on it. I would like to clean this wall and leave it natural. My husband is keen to paint it.

Could you recommend a cleaning product which won't leave streak marks and leave it as clean as possible?

A. I assume that this is an interior wall. Cleaning can be an issue for interior concrete, as most concrete cleaners need to be rinsed off with water. The best product to remove oily stains is Resene Heavy Duty Paint Prep and Oil Remover but use for interior cleaning will be a challenge.

Q. We live in Fiji. The white oil based paints on our window and door frames are constantly going mouldy. This is a real problem because many are extremely difficult to reach to clean. Why does this happen and what can be done? It is a huge job if we have to repaint. If we used water based or low sheen, would we still have the same problem?

A. The occurrence of mould growth on a painted surface is related to the environment and not the paint type, although low gloss paints do appear to be more susceptible to the establishment of mould growth. In Fiji the climate does see increased biological growth on exterior painted surfaces. Application of Resene Deep Clean will give ongoing control of mould growth and is slow acting; biological growth is killed and then washed off with rain. I would say that a biannual application would be a sensible approach.

Q. I have a ply exterior weatherboard that has previously been sealed with Resene Woodsman, I am wanting to redo this with a dark colour but I notice I have what looks to be mould (black) on the wood near the ground and also in shaded areas. I read about mould killer - is it spray application or brush on please?

A. You can use a small garden sprayer to apply the diluted Resene Moss & Mould Killer to areas of mould. Make sure your wear protective clothing and gloves and eyewear to apply the product as the solution is bleach based and alkaline.

Q. I was wondering about using your Resene Deep Clean? Does it contain anything that may affect butynol underneath porous tiles?

A. Resene Deep Clean can be used on tiles and is a mix of surfactants that will not affect the butynol.

Q. We are about to sell a rental property. Can you please give me advice on removing mould that has come through on a painted toilet cistern?

A. I recommend that you treat the mould with Resene Moss & Mould Killer diluted and used to label directions. However if the mould is growing through the paint then it may need to be stripped back to the level, treated with the Resene Moss & Mould Killer before repainting.

Q. Prior to repainting, can I wash my exterior stucco walls with Resene Roof Wash and Paint Cleaner? I have a new container of it that I would like to use. Does the wash then need a rinse?

A. We recommend using Resene Paint Prep and Housewash diluted and used to label directions for preparing painted stucco, and yes, it does require a thorough rinsing with water.

Q. I'm preparing a house to paint and it has lots of trees around it, so it has a mould problem. Should I treat with Resene Moss & Mould Killer before or after painting or what should I do to stop it?

A. Yes, treat all areas with Resene Moss & Mould Killer diluted and used to label directions. After painting, apply Resene Deep Clean diluted and used to label instructions either at the beginning of spring or autumn. If particularly bad, a twice yearly application of Resene Deep Clean may be required.

Q. Can you tell me if Resene Paint Prep and Housewash will remove salty sea spray residue from painted weatherboards and if not do you have something that will?

A. Resene Paint Prep and Housewash is designed to remove surface chalking from a painted surface. It will remove some sea salt as any water washing will. Prolonged rinsing with water is the best way to remove salt. After washing down you could apply a coat of Resene Enamel Undercoat over a sound surface prior to topcoating with two coats of waterborne topcoat.

Q. I am searching for care and cleaning instructions for Resene Colorwood stains.

A. A clear varnish system is recommended to be applied over a surface stained with Resene Colorwood. For this reason the stain should not need maintenance but the clear coats may. Given that the stain system is usually applied to an interior substrate the only maintenance that should be required is to keep the surface clean and apply a maintenance coat of the clear topcoat on areas showing loss of clear film due to wear.

Q. I painted a bedroom about a year ago after stripping the wallpaper and using Resene Broadwall Wallboard Sealer. Inside the wardrobe I did not strip the paper or use Resene Broadwall Wallboard Sealer, and just painted one coat of paint over the old wallpaper. There is still a strong paint smell coming from inside the wardrobe. Should I strip the painted paper down to the wall surface and start over or try another coat of paint or is there a better solution?

A. I recommend that you wipe the painted surface down using Resene Moss & Mould Killer diluted and used to label directions then ensure good ventilation for at least a week. It is possible that the odour may be from mould infestation as any paint odours should have long since dissipated.

Q. What product should I use to clean/treat mould off a Butynol deck, prior to painting?

A. For a quick result use Resene Moss & Mould Killer, or if you can wait Resene Deep Clean.

Q. For a building built with concrete tilt slabs and painted, how frequently do you recommend washing?

A. We recommend an annual wash down, using Resene Paint Prep and Housewash, paying particular attention to areas not subject to regular rain washing.

Q. I have a number of plain, unglazed Australian made terracotta tiles left over from a project that I want to use in a new project. They have been sitting in plastic bags outdoors for 2 years and there is moss and mould on them, particularly along the edges. I am cleaning them carefully with a soft brush and water, but I feel there is likely to be some mould/moss residue. Can you recommend a product that would be safe to use on these tiles that would not bleach or otherwise discolour them?

A. Not sure if the tiles will change colour if subject to bleach solution, if not then soak the panels in Resene Moss & Mould Killer diluted and used to label directions for 24 hours then remove and soak in a number of water changes to remove the bleach residues. Then allow to dry.

However if bleach does caused an issue then the only alternative is to saturate the tiles with diluted Resene Deep Clean and leave for a week then soak in water as above.

Q. I have moss/mould/lichen on my outdoor texture surface on my house. As we are on tank water I’m not sure what to use! It’s on a high area of the house, chimney, etc. Any chance of brushing it to kill it?

A. Unfortunately the only way to control these growths is by chemical intervention. Waterblasting can remove biological growths but does not remove spores and regrowth will re-occur. Removal of lichen after treatment with a chemical agent still takes time for the lichen to detach for removal. Sorry but no easy solution when you are collecting drinking water from the surfaces that have bio growth.

Only possible option is to treat areas with concentrated Resene Moss & Mould Killer and leave for two weeks then waterblast, however this will require disconnection of pipes to tankage during this time. However this is not a long term fix.

Q. On one side of our house the weatherboards are mouldy. I have tried waterblasting it which didn’t seem to help.

A. Mould growth usually appears on the south side. Waterblasting alone will not remove or prevent mould growth. Areas of mould growth must be treated using Resene Moss & Mould Killer diluted and used to label directions. For ongoing mould control apply Resene Deep Clean diluted and used to label instructions at the beginning of spring or autumn.

Q. Our blackboard paint wall has been used a lot and has some residues of chalk. What is the best way to clean these off?

A. Use a soft lint free cloth and Resene Interior Paintwork Cleaner.

Q. Greetings, today we were sold Resene Moss & Mould Killer for our deck, however it seems it may break down the cellular fibre of the timber and I should use a sodium per carbonate material.

A. We are very familiar with sodium per carbonate having researched it in the past. It is not as innocuous as it seems! It is a strong oxidizing agent and an irritant which is not stable in the presence of many organic materials.

It is best looked upon as a mixture of sodium carbonate (washing soda) and hydrogen peroxide - which, like sodium hypochlorite, is a bleach. It also has a similarly high pH (10.5 for a 1% solution) climbing to 11.5 (and higher) as the hydrogen peroxide depletes leaving an enriched level of sodium carbonate on the surface.

Resene Moss & Mould Killer will certainly bleach the timber (as natural daylight does) along with its ability to kill moss and mould. It does not damage the wood fibre. At the dilution used it will dissolve any surface wood sugars (which are deleterious anyway) and possibly some lignin which has escaped being degraded by U.V. This is a positive feature as all of our research has shown that a slight opening of the surface (especially with new timber) enhances the take up of the decking oil/stain and gives significantly improved durability.

Q. I am redecorating my bedroom and I have had mould on the wallpaper which I am stripping off. Can you recommend something to kill the mould before I paint?

A.Treat with Resene Moss & Mould Killer diluted and used to label directions. Take care not to splash onto carpets or furnishings as the diluted material is strong bleach.

Q. We recently coated our ply wall with Resene Woodsman Wood Oil Stain. When the scaffolders took some of their scaffolding away they spilled a whole lot of rusty water on the ply. It wasn't discovered until a few days later. We then tried to wash it off with water but that wasn't successful. Is there anything that you can recommend that we can try to get the rust marks off?

A. There is no easy way to remove the rust staining as the stain was so fresh. The traditional way to remove rust stains was to treat the affected areas with a diluted solution (suggest 1%) of oxalic acid.

Q. Can Resene Moss & Mould Killer be left on for more than 48 hours?

A. Yes the reaction is usually quite quick; you must thoroughly wash down any rusted surfaces prior to painting with fresh water.

Q. What is the best product to use when prepping the exterior of a house to restain?

A. We recommend Resene Paint Prep and Housewash.

Q. I have to repaint the entire house. The current paint is in good condition. I am repainting because the paint is dirty, has non erasable pencil marks and is chipped. I don’t like the colour. The kitchen had really greasy walls. The cleaners used diluted caustic soda (sodium hydroxide) to clean the walls. They used this process: Wipe with a sponge dipped in diluted caustic soda solution, scrub, and wipe off dirty liquid from walls with cloth. Wipe with sponge dipped in water then wipe off water with cloth. Let dry. Can I repaint these walls now?

Will any remaining trace of caustic soda solution create problem for paint now or a few years from now?

A. All residues of sodium hydroxide need to be removed before painting. This can be tested using pH paper available from a swimming pool supplier. The reading should be close to 7.

Q. Is Resene Mould & Moss Killer the best thing to use on Decramastic tiles to keep them clean and free of moss and mould or is there another product you would recommend?

A. We recommend Resene Deep Clean. This is a cleaner that works over time with the weather to clean the surface.

Q. We have a lot of external painted (white) timber work on our property and we want to clean it. Can you please recommend what product to use to clean the paintwork? We are close to the ocean so are not sure if that affects the type of product we use.

A. Our cleaning product for paint work is Resene Paint Prep and Housewash. If there is mould present then use Resene Moss & Mould Killer for these areas and then wash down with the Resene Paint Prep and Housewash. Dilute and apply product following label directions.

Q. Can you use Resene Moss & Mould Killer on a COLORSTEEL® Versatile garage?

A. Diluted Resene Moss & Mould Killer can be used to treat moss/mould on this substrate. Just take care to avoid application to glass.

Q. I spent all weekend building a shed for storing hay for our horses. Today my wife decided to paint the outside of it. She picked up a tin of what should have been deck stain from my garage and proceeded to paint the walls with used engine oil. (My fault for not getting rid of the tin after giving my ute an oil change). The exterior walls are h3.2 treated plywood. Can this be painted over with anything? And what do I need to do now?

A. Definitely not an easy one to solve. To paint or stain the oil will have to be removed from the timber. The only possible way would be to treat with Resene Emulsifiable Solvent Cleaner. But this does involve using a solvent and then washing off with water so ground contamination is unavoidable.

Q. Could you advise as to what I should use to remove old paint from metal window latches?

A. Not an easy undertaking but a 3M Rust and Paint Removal Disc may work. This fits on an electric drill.

Q. Can you recommend a rust treatment for rusted flashings, nails etc. I have been using a rust killer, but after following the directions to the tee the rust has started leaching through our new paint again!

A. 'Rust kill' products are often not as effective as claimed. We recommend Resene GP Metal Primer for priming areas of corrosion. Wash the areas to be painted with Resene Roof and Metal Wash diluted and used to label instructions then remove as much rust as possible by wet sanding (wet and dry sand paper) or using a 3M Rust and Paint Removal Disc. Then apply the primer, a second coat for heavy corrosion. Rust cannot be stopped but hopefully the corrosion rate can be slowed down.

Q. We have just removed a fruit salad plant from the side of our house, the ones with the gigantic leaves. Unfortunately it had clung to some of the blocks leaving some thin bits of tendrils/aerial roots on the bock, similar to ivy. The paint on the blocks is your Resene Lumbersider (Resene Turtle Green) and I'm going to do a touch up but am not sure how to go about it. They don't seem to want to scape or pick off. It's not in an important place, but obviously I don't want it to look grotty!

A. We have a similar issue with ivy tendrils. Only way that I have found is to treat the areas with residual vegetative material with Resene Moss & Mould Killer following label directions, then using a 3M Rust and Paint Removal Disc, carefully attack the remaining tendrils.

Q. Can Resene Timber and Deck Wash be used on a deck of oiled Kwila before re oiling? If no, what is the best product for this job?

A. See no reason why not. If the tannins from the Kwlia are still present then the cleaner may remove them which may change the timber colour.

Q. What can I use to wipe dirty hand marks off Resene Zylone Sheen? The paint has been on for two years.

A. We recommend Resene Interior Paintwork Cleaner.

Q. Would Resene Deep Clean be suitable for use on a tar sealed driveway?

A. Yes you can use Resene Deep Clean on almost any exterior surface.

Q. Have just bought a house. They have had a bbq on the deck so there is fat and dust mixed together on wooden weatherboards. How would you recommend to clean this? The paint job on the house is in good condition.

A. Try a light bristle scrub down using Resene Paint Prep and Housewash. Sounds like you need a light detergent to get rid of the contamination. As always, follow the instructions on the pack and trial an 'out of the way' area first to ensure you achieve the desired result.

Q. My kitchen, dining, lounge area is open plan and a rather large space located in Cromwell (hot summer, cold winter). The house is about 18 years old. The ceiling is marked with what appears to be grey dust that forms on the plasterboard along where the beams are above in the ceiling cavity. It doesn't wash off and I suspect it may be static (like dust on TV screen).

What prep and product do I paint with to prevent this happening after I redecorate?

A. Unusual effect, cannot see why dust would be only present on the beam lines. If it was dust/dirt it should wash off. The other possibility is mould growth. There can be a thermal difference between the plasterboard directly attached to the beams and the hang free plasterboard. This can result in the accumulation of moisture along the beam line which may give conditions for mould growth. Is there insulation in the ceiling? To check if it is mould try wiping an area with a cloth and bleach - be careful not to drop any bleach onto floor coverings etc. If it is mould the bleach should bleach out the given colour.

Q. How do I remove tarnishing from copper?

A. You can use white vinegar and salt to remove tarnishing from copper; however it will return especially in fully exposed exterior areas. To reduce re tarnishing you need to apply thick layer of an NFM (nonferrous metal) lacquer clear.

Q. Three months ago a man painted one wall of a sunny bedroom for me. The wall was previously coated with a metallic silver finish and had quite a few staple marks etc. He plastered, sealed and topcoated with two coats. It looks good but there is an awful paint stink. I've tried onions, baking soda and charcoal but still the smell builds up on hot days. I think he didn't let the sealer coat dry off enough. I don't know what the sealer coat was. I am in the process of trying to sand the wall back. Is there anything I can reseal it with to stop the smell or would vinyl wallpaper do it?

A. The odour may be due to paint degradation of the wet paint prior to or at application. Suggest that the walls are wiped down with Resene Moss & Mould Killer diluted and applied following label instructions as a first step and ensure that the room is well ventilated. If this does not remove the odour then it is unlikely to be associated with the paint but with another cause.

Q. Can Resene X-200 once dry and cured be waterblasted in future to keep it clean?

A. All depends upon the waterblasting pressure and how far from the surface the tip is held. Low pressure washing (<3000 psi) with the tip held away from the surface should not be detrimental to the coating adhesion. For cleaning a scrub down with Resene Paint Prep and Housewash and a water wash down is all that should be required.

Q. Can you leave Resene Moss & Mould Killer on your walls/ceilings (on painted Pinex) for longer than 48 hours before washing it off? Is it okay to leave it for 5 days or more?

A. Yes, this is fine.

Q. We have had a fire which has caused minor smoke damage to some apartments. The fire was outside the building so the smoke entered via open windows and ranchsliders. Can you advise the correct specification and process for repainting with Resene products?

A. Wash down smoke damaged areas using Resene Interior Paintwork Cleaner following label directions than apply a coat of Resene StainLock and finish with two coats of any Resene interior wall paint.

Q. I live in a 20 year old Lockwood and want to remove grease stains from the planks near my stove. The area was cleaned with sugar soap and sanded and appeared clear of any marks. Two coats of polyurethane was applied but the grease marks have reappeared - even worse than before.

A. It is possible that the grease had penetrated beneath the original varnish. If you used a solvent borne varnish the new varnish could have dissolved the grease and brought it to the surface.

Q. I am planning to paint the cedar exterior of my house this summer. The house was built in 1989 and I was just after some advice about the best way to wash cedar before restaining. I heard waterblasting will damage the wood and the other option was a chem wash but I've heard these can be quite harsh.

A. Scrub down with Resene Timber and Deck Wash diluted and applied following label directions.

Q. The previous owners had an automatic Ecomist can which has left 80cm stain down the wall. I have applied three coats of a stain blocker, primer sealer (waterbase) and then three coats of topcoat. The stain is still leaching through. Can you recommend any further treatment to hide the stain? Washing and sanding didn't work which was why I applied the stain blocker.

A. Normally the treatment you have used does effect stain blocking. Another option would be to wipe the surface down with Resene Emulsifiable Solvent Cleaner, then wipe down the area with water and a cloth until the wash water is clear. This will require water changes. Allow to dry then reapply the Resene StainLock.

Q. How do we successfully remove mould from wallpaper without discolouring, tearing or lifting the wallpaper? Ideally we would like to paint over the wallpaper; however we have one room where mould is quite bad.

A. Resene Moss & Mould Killer is the only mould killer we have and it is bleach based, so cannot predict if it will bleach colour from a paper even when used as a dilute solution. You could try it on an area of inconspicuous paper as a trial.

Q. I am using your metallic effects paint on a shed and have applied a primer of Resene Vinyl Etch before applying the metallic paint. It looks amazing but how long before full curing is achieved? I can see that moisture (condensation) is causing 'streaks' to form even after a minimum drying period of a few hours. Will water/moisture ALWAYS cause damage to the appearance even after the maximum dry time?

A. The issue you describe is surfactant leaching and only occurs when the paint film is not sufficiently cured to resist water or condensation. Touch dry does not mean cure and also the dry times we give are always for a minimum air temperature of 18 degrees C. Assuming the film has dried under the correct conditions the leaching should only occur in the early stages. However you will need to wash the surface down using Resene Paint Prep and Housewash to remove the surfactant from the surface.

Q. What is the best way to clean marks and stains from a painted wall? Also which type of paint is more suited to homes that have sticky-fingered children?

A. You can clean your paintwork using Resene Interior Paintwork Cleaner and a soft cloth. Using light strokes, thoroughly wipe the area to be cleaned turning the cloth frequently to maintain a clean edge. Wipe away any excess solution. To achieve an even finish, dry the surface with one final wipe using a soft dry lint-free cloth in the direction of the paint flow. If trying to remove a localised mark, start from a radius wide of the mark and work towards it. This will minimise any 'tide mark' that might develop.

Be aware that walls, like windows, can accumulate a faint layer of dust or grime. A seemingly minor job of cleaning a small spot can lead to a major cleaning job. If unwillingly caught in this predicament, a feather duster can sometimes minimise the boundary between the cleaned and uncleaned areas.

Paints to use: Waterborne enamels, such as Resene SpaceCote Low Sheen, are more durable and easier to clean than standard acrylics without leaving marks. On trim and joinery opt for a semi-gloss waterborne enamel, such as Resene Lustacryl. For your ceilings opt for a waterborne enamel, such as Resene SpaceCote Flat, rather than a standard ceiling paint. You will then be able to wipe off flyspots without damaging the paint finish.

It's best to wait four weeks to give the paint plenty of time to cure before you start cleaning it.

Q. I have fitted new primed MDF skirting in my living room. After two months a dark green dry dust appeared in different areas of the skirting. It rubs off easily. Any idea what has caused this and how to prevent it?

A. One of our team who has lived in London made the comment, dark green dust sounds like it could be mould. Mould growth is indicative of damp/dark/poorly ventilated areas. We normally recommend you treat mould with a hypochlorite mould killer, such as Resene Moss & Mould Killer, then repaint.

Q. As property managers we are always having to deal with scuff marks on painted walls! Abrasive cleaners leave marks and dull the paint. Please advise an effective method for our tenants to use.

A. Removal of scuff marks is a function of the material causing the marking and the resistance/toughness of the paint finish. Unfortunately there is no single non-abrasive cleaner that will remove all marking without causing a level of damage to the paint finish.

The Resene waterborne enamel wall paints are more resistant to damage during cleaning than paints formulated on conventional acrylic resins. As a general rule the higher the paint gloss level the easier cleaning is; current preference for many is to use low or flat paints as the wall finish. For details on how to clean the surface see the Resene Caring for your paint finish brochure available on this website.

Q. How do I treat moss and mould?

A. Moss and mould problems:
On painted surfaces, mould looks like dirt, and frequently the two cannot be visually distinguished.

The most common species are black, but others can be brown or green. By wetting the surface and rubbing, mould will show up as slime.

Mould is a major cause of paint disfigurement. It destroys the paint's fresh clean appearance, and if left unchecked it shortens the life of the paint film. Unless removed within a few months of its appearance, mould penetrates the body of the existing film and once firmly established, will grow through subsequent paint coatings, impairing adhesion and ruining the appearance of the paint work.

What to do:
Thoroughly clean down to remove all loosely adhered material. Treat areas of moss or mould infestation with Resene Moss & Mould Killer, correctly diluted (see pack) with clean water. As soon as the mould has been completely de-colourised (which indicates it has been killed) wash thoroughly with clean water to remove residues.

Once the moss and mould is completely removed and the surfaces have been correctly prepared, proceed with the Resene recommended paint system.

Mould is likely to occur in humid areas, such as bathrooms. Always make sure areas like these have adequate ventilation otherwise the mould is likely to reoccur.

Resene has a range of Kitchen & Bathroom products formulated with anti-bacterial silver and Resene MoulDefender to help inhibit bacteria and mould growth.

Q. We have recently moved into a two year old house with painted internal walls. The walls have marks on them and I would like to know how to clean them off without having to repaint the entire house. Can you suggest a product to use that will not damage the surface?

A. We recommend you try Resene Interior Paintwork Cleaner, available as a concentrate or pre diluted. Click here to view our advice on caring for your paint finish.

Q. What can be used to remove tannin stains from galvanised metal? The tannin comes from new hard wood exterior stairs onto the stringers.

A. If the galvanising is unpainted you should be able to remove the tannin stains by wiping with a water solution containing 15% cloudy ammonia or a 10% solution of washing soda.