Advice on best product to paint on wooden window frames

[Confiteor]

Hello

My newish (to us) house is around 15 years old, and has wooden-framed double glazing.

They were never maintained by the previous owner, and so I have had to sand them back to the wood to get rid of all the peeling stain and get back to a good, level base layer. They were very weathered, but the wood itself is still completely sound.

I'm looking for advice on the best product to use to re-stain the frames.

I have a Cuprinol five-year stain from another job that I could use, but I'm wondering if there is anything better. The Cuprinol claims that it doesn't need a primer to be applied first.

Since it is taking me a long time to sand them back, I'd like to finish the job properly by applying the best product. I'm hoping that if I do the job well this time, I can save myself a lot of time in future by only needing to freshen up the stain every other year or so. Sanding right back to the wood has been a nightmare of a task, and I hope I won't need to do so again.

Cheers.

 

[Watchmaker]

As an amateur, and with many years behind me carrying out that chore of painting, I would highly recommend these new type of flexible finishes.
Paint does not last very long before it needs re-doing and the old type of varnish would start to split and peel the moment the sun got onto it. Sadolin is the brand which I have used but, no doubt, the Cuprinol product is similar. I have found that it is so easy to apply, needing no undercoat or primer and, when it needs freshening up, all that is required is a quick rub over with, say, a soft rag with a small amount of turps, and another coat can be applied. It used to take a week to rub down, fill, prime, undercoat and gloss when painting the average house. Now it can be done in a day. I don't know it's chemical compostion but, it does not flake or peel and, most important, it does not need re-doing every couple of years or so.

 

[McD]

I've just had a couple of windows made and the joinery recommended Sadolin. Basically they put on a base layer which they describe as micro-porus allowing the wood to breathe whilst protecting it.

I then bought the the top coat (apparently the clear one does not have any UV protection) and gave it two coats. No problem and I hate painting.

 

[Antwerpman]

what you need is this stuff

http://www.holkham.co.uk/linseedpaints/

it takes some preperation on the first application but you have done the hard bit of stripping off the old paint, so the rest is just applying the new.

Once on all you need to do is apply some warmed Holkam linseed oil after 6-7 years to freshen it up, then after another 6-7 years a new layer of paint and continue this way ad in finitum

I have used it on my driveway gates and am in the process of putting it on all my windows (100 years old) and it really is somthing completely different from modern paints - it allows the wood to `breath` and really soaks in to the wood, bonding with it in such a way you cant peel it off with your finger like you can with many modern paints.

Downside is a slightly higher initial cost and limited range of colours (but you can mix to achieve yoru own) but the lifecycle costs in materials and more importantly your time and effort are much less

Hope it helps and worth considering....

 

[DJG]

I'm looking for advice on the best product to use to re-stain the frames.

I've no personal experience of either Sadolin or Cuprinol, but I've been told Sadolin is better, though I don't now remember why that was.

However, I'm in a very similar position as yourself, my windows had been poorly maintained by the previous owner. A neighbour who is an architect highly recommended Butinox paint. It's expensive (I think I paid £35 for a 3-litre can in my local hardware store) but fantastic.

There's a lot of work at first to remove all trace of the old finish, but repainting is very quick and easy. It goes on easily and looks great.

Highly recommended.

 

[masona]

Another one I can recommend is Tung Oil, do a search here on Tung Oil, been mention a few times. So easy, wipe it on with a rag!

 

[JohnD]

I wonder if one of these oils would be suitable for hardwood door sills, exposed to the weather? Anyone tried it?

 

[masona]

It's the best treatment, wood need oil therefore can breathe as well. China use tung oil on their boats for years protection against seawater!

All my windows, doors and summerhouse is treated with tung oil.

 

[JohnD]

I sanded my sills down yesterday to remove the weathered surface, and gave then a good drenching with Cuprinol Clear Preserver. While that's drying I had a look round my little town, no Tung oil, but found Linseed and Teak oils.

Would they be any good? I imagine that once I have oiled the wood I will never be able to stain or paint it in future, because the surface won't stick.

 

[biffvernon]

I make oak windows and, when I paint them at all, only use real linseed oil paint.

You can certainly put linseed oil paint over wood that has been oiled. When using a linseed paint such as the Swedish Allback sold in UK by Holkham Paints and recommended by Antwerpman, you first coat the wood with linseed oil before applying the paint. Tung oil, the main ingredient of 'Danish oil' is not very different from linseed.

Modern alkyd resin based paints - all the ordinary oil gloss paints for exterior use - form a waterproof film on the wood. After a couple of years the differential movement between wood and paint cause cracks in the paint layer which allow water in. Being waterproof the paint stops the wood drying out. The wet wood then starts to rot and the paint flakes and drops off. Modern paint is largely responsible for the poor performance of wooden window frames in recent decades.

Real linseed oil paint soaks into the wood instead of just forming a surface film. The paint sheds the rain but is vapour permeable so wood stays dry and does not rot. It never flakes off but the surface slowly erodes. The surface can be revitalised by a coat of linseed oil after several years and, according to Allbacks recommendation, should be given another coat of paint after 14 years. A 14 year maintenance cycle coupled with wood that does not rot makes real linseed oil paint a very cheap treatment.

Linseed oil paint is based on a sustainably grown renewable resource. It contains no VOCs and is not hazardous in manufacture, application, use, and ultimate disposal. Modern alkyd resin paints are based on the petrochemicals industry and produce hazardous materials at each stage of their manufacture, use and disposal.

The only downsides to real linseed oil paint are that the slower drying times mean that the decorator can't slap on three coats in a day and move on to the next job tomorrow and the paint manufacturer does not make much profit because the customer does not return after three years for another can.

Remember that the most expensive paint is cheap paint.

 

[JohnD]

Thanks, that's interesting. Can I just oil the wood instead of painting it (I previously had a translucent stain like a satin varnish, and the doors and cladding are stained, not painted).

I think I saw Danish Oil locally when I was looking round, but had assumed it was for indoor furniture.

 

[masona]

JohnD,

The difference with Tung Oil to others oil treatment is a slower drying out period therefore penetrating deeper into the wood longer. I've found Danish Oil dried out too fast but still a good oil teatment. Tung Oil is available online, type in Liberon Tung Oil in google.

 

[JohnD]

Thanks!

How often should I re-apply to my outside door sills?

I've found "Liberon" on the Agwoodcare website now, I see they also do a Decking Oil, it doesn't say of this is Tung or something else (but is much cheaper so I presume not the same thing).

 

[biffvernon]

Yes, I think with Danish oil they add some driers to the tung oil to make it set quicker. Probably MnO2, though they don't admit the ingredients on the tin. Boiled linseed sets faster than raw linseed so the potentially deeper penetration of raw may be the reason why it is recommended. I'd be interested to see any serious research that demonstrated a difference though. The difference in finish appearance between linseed and tung is rather subtle. Tung seems to soak in without leaving a shiny surface while linseed gives a slightly more glossy finish. I usually use tung on the inside of an oak window where I want it looking very natural while I use linseed on the outside as the surface film sheds the rain a bit better. I'm not claiming I could always tell the difference though.

 

[masona]

How often should I re-apply to my outside door sills?

If it's for the first application then 50/50 with white spirit daily for the first 7 day, then once a week 70/30 ratio say next 4 weeks then 100% full coat once a year.