preparing window frames for finish coats

[diynovice99]

Hi all,

I moved in with my mum a while ago and have been renting out my flat. The management agent of the flat has requested that I prepare the 2 small wooden windows (the other windows are PVC) for 2 coats of top coat this spring/summer and has noted there may be some wet rot, although they weren't 100% sure. My mum lives about 100 miles a way from my flat, so I'm aiming, if possible, to do the work in a day. Assuming there is rot, I assume I need to:
- gouge out rotten wood.
- apply hardener followed by a wood filler
- apply 2 coats of primer/undercoat
- possibly apply a top coat to protect the wood until the professionals do their work?

My questions are:
- Do the steps I give above sound right?
- Am I being realistic by trying to do it in a day? I'm aim to start about 9am.
- Would quick-drying paints be suitable for the job and give me a durable finish? And can you recommend specific products? The 2 windows face SE and NW if that has any bearing.
- My flat is in the south (Hertfordshire). Do you think I could do this in early March, or should I wait a few weeks?

If I don't do the work, the management agent plans to charge me £200 a window, which as I am sure you'd understand, I'd rather avoid.

Many thanks for your help!
kind regards.

 

[sparkwright]

It seems cheeky they expect you to do the preparation, and someone else to do the finishing coats.

What you suggest sounds fine, but you MUST rub down all of the surface before applying any paint.

To get a job completely done in a day, you could use Sadolin Superdec, available in white. It dries very quickly, and lasts a long time. Even the worst paintwork can be covered in three or four coats. This can be used as a finishing coat as well, available in satin or gloss. It is water-based.

If you did want to apply oil-based paint, lightly rub down the sadolin and apply oil-based undercoat.

 

[sparkwright]

As you want to do this in a day you will have to work methodically. This will involve alternating between both windows.

Scrape out the rotten wood first then, then apply the hardener so it has time to dry.

Start scraping off any loose paint and sand down.

Apply the two pack filler, assuming the hardener is dry.

Apply the Superdec (or primer, depending on what you choose to use) to bare wood.

Sand filler, apply more filler if necessary.

Begin putting on the coats of paint.

 

[sparkwright]

Yellow frog tape may be useful to reduce cutting in, this is up to you, depending on your skill.

 

[diynovice99]

Many thanks for your detailed and informative response, sparkwright! It sounds like it should be doable, but that I need to draw up a detailed plan and work to it.

Is this the superdec product you are referring to?:
https://www.sadolin.co.uk/products/sadolin-superdec-satin-opaque-wood-protection/

If so, I notice it states a drying time between coats of 16 hours, which may make doing the work in a day awkward. Is 16 hours over-cautious?

I guess at the least I need to apply a primer and 2 undercoats. All of which, I understand from your response, I could use the above product for.

Depending upon the delay in the agent's decorators applying their 2 top coats, I assume I should also consider putting at least one top coat on to keep things protected from the elements. Am I right in this assumption, or am I adding extra work for no benefit? - I guess I'm asking if the Superdec could be left for, say, a month, without a top coat.

Finally, if the decorator is using oil-based top coats, does this change what products I should be using for my preparation? Or, once I've done the 'base' work (with water-based products), is it standard practive for them to apply the appropriate undercoats for their oil-based top coats?

Many thanks & kind regards.

 

[sparkwright]

That is the paint, and it does in fact say 16 hours between coats.

Assuming you are doing this on a fine day, I wouldn't worry about the drying times - nothing seems to go wrong with this product.

If the final coats are to be oil-based, water-based products will do for the first few coats, to get the colour and protection, then give a light rub down and use an oil-based undercoat.

 

[diynovice99]

Much appreciated, sparkwright! I'll look to get this done in the next couple of weeks and will follow your recommendations.
kind regards.

 

[gc1967]

If you want to get it all finished in a day you wont be using oil based paints because of drying times, putting on too many coats in 1 day is wrong, they should be cleaned down, filled, rubbed down, 2 oil based undercoats and 1 oil base gloss.
Water based paints are in my opinion rubbish, show every brush mark and it wont last long on outsides, this is my own personal opinion, I have been a Painter and Decorator for 33 years, I know I will have to get use to water based paints as oil based paints will be phased out in the next few years - fact - straight from dulux

 

[diynovice99]

Thanks for sharing, gc1967. I guess I will either have to a) use superior oil-based paints and do the work over several days or b) go down the water-based route and mitigate the risks as much as possible by using the best product in the best fashion. Sadly, although I'm all for doing the best job, I just don't see a) being a feasible option for me given my circumstances, so I'll have to go with b) and make the best of a bad situation. Any guidance with this route would be most appreciated.
kind regards
Neil

 

[Notch7]

Thanks for sharing, gc1967. I guess I will either have to a) use superior oil-based paints and do the work over several days or b) go down the water-based route and mitigate the risks as much as possible by using the best product in the best fashion. Sadly, although I'm all for doing the best job, I just don't see a) being a feasible option for me given my circumstances, so I'll have to go with b) and make the best of a bad situation. Any guidance with this route would be most appreciated.
kind regards
Neil

The argument re oil v water based isnt that straightforward. Waterbased based paints can last for a long time. All new joinery is finished with water based products, Ive made joinery that after 8 years with waterbased finishes is still in good condition.

Bear in mind waterbased paints want 10 degrees or above to cure, so painting in cold condition will slow or stop cross linking.

 

[diynovice99]

Thanks, Notch! So the situation isn't as bad as I thought. Given your comments on temperature, I'll see how far into the spring I can push the work back.

 

[opps]

All new joinery is finished with water based products

Primarily because waterbased paints are safer to use in workshops, and not because they provide equal or better longevity.

This week I finished repainting 6 (year old?) windows that were factory sprayed with waterbased paint. Prep took 30% longer than it would have taken if they had been painted with oil based paints. In many places trying to feather the paint resulted in the paint coming away from the wood.

Personally I suspect that part of the problem is that spraying the first base coat doesn't provide as good a key as brushing the first base coat. The other part of the problem is that waterbased paints do not like being sanded.

I use the Dulux Trade Weathershield system, the preservative primer (post 2010 VOC compliance) is now waterbased and the degree of grain raising on pitch pine can be embarrassing. I some cases I just use solvent based wood preservers instead- the down side is that you have to wait much longer before overcoating but you don't get grain raising.

 

[opps]

Bear in mind waterbased paints want 10 degrees or above to cure, so painting in cold condition will slow or stop cross linking.

True. However it is worth noting that ideally the temperature won't be less than 10 degrees for at least 12 (?) hours after the paint has been applied to allow the molecules to coalesce. If it is 10 degrees at midday, it is unlikely to be 10 degrees at midnight. (Admittedly I plucked the 12 hour figure out of the air- none of the paint manufacturers seem to offer guidance).

 

[diynovice99]

Thanks, Pitch. So if I am to use water-based paints, I need to hope the original paint is oil-based, brush the paint on and sand sparingly between coats.

Sounds like the Dulux Trade Weathershield primer has a serious flaw. However, other than the raised grained, would you say it was "acceptable"? Or do you think the likes of Superdec are superior?

kind regards.

 

[diynovice99]

Oops, sorry, I addressed my last message incorrectly to Pitch. I should have said (and thanked!) opps.