Paint spec for renovated sash windows

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however for someody not in the trade the easiest to get hold of and good prices are the Mighton paints which come from Holland, Anker Stuy Verven BV. Ive sprayed this paint a number of times and its pretty good, also quite soft and flexible
This is interesting, they sent me a tub of their primer which I tried this week (brushing ) I was not impressed with it and found it pretty watery and not very opaque, needed 3 coats to get a satisfactory finish on a sash I was repairing. I would compare it to Dulux waterbased or maybe Leyland.
Maybe it sprays better.
 
Thanks Ollie, just wondering when you say to dust the putty of with plaster, what particular plaster are you referring to, gypsum multi-finish?
Multi finish for preference but you can use drywall adhesive or even a powdered filler like Toupret or something.
I think you are really supposed to use what they used to call whiting which I believe is finely ground chalk.
 
This is a very individual opinion so here goes. Oil based is best on pine especially old rough pine. Stick with oil based right through. The system is knotting, primer, undercoat, undercoat , gloss. In order 1.knotting patent thick knotting or 2 coats of bin. Do not sand. Just around knots of course. 2. primer very important I prefer sandtex flexi primer/undercoat but as an undercoat it's a bit thin. To primer especially if you've had these dipped or any chemicals potential adhesion problems add a good dash of owatrol.
3. Undercoat on old work needs to be thick and to rapidly dry, build, then be easy to sand. If yours are indeed stripped and clean the stick with sandtex flexi undercoat if there old and chipped/cracked use coverstain as oits much thicker and dries in 2 hours. This is in essence filler paint.
4. Gloss I like sandtex they do a satin as well. Its pre mixed.ive been using dulux trade weathershield this week and whilst fine it's not as forgiving as sandtex. It's got lots of driers so skins in the tin an takes forever to mix completely being mixed in the shop. To thick and it wrinkles so it needs some owatrol and some white spirit. All oil based paints are needing black bristle brushes ideally or failing that Purdey monarch Pro extra. And a paintmate to keep them wet. Every few hours of painting rinse your brushes in white spirit otherwise they drag. Avoid plastic caulk and fillers esp on bottom edges.Use putty if you've got time(toupret can be painted in 6-8 days) gras a lacquer on small shallow fills. But undercoat your friend on old stuff.
 
By all means use linseed paint. Water based tends to raise the grain forever then is thin and hard to sand and the top coats are transparent. But it's quite flexible if prone to adhesion issues.
 
Zinsser AllCoat does seem to be the decorators favourite paint at the moment.

I don't like adding more options but if you do go down the oil based route Aluminium primer is worth looking at.

Even if you do use proper putty to point you can still use something like Timba Glaze to bed the glass in, it sticks the glass in nicely, glass just puttied in with no pins always makes me nervous.
 
Zinnser allcoat seems a decent drop but is very thin with poor cover. Ankerstuy make a filler primer that's a very thick product. It helps to build which is an area water based paints are bad at. Also I use coverstain thinned as a primer before water based as it stops the terrible grain raise using water base.
 
This is a very individual opinion so here goes. Oil based is best on pine especially old rough pine. Stick with oil based right through. The system is knotting, primer, undercoat, undercoat , gloss. In order 1.knotting patent thick knotting or 2 coats of bin. Do not sand. Just around knots of course. 2. primer very important I prefer sandtex flexi primer/undercoat but as an undercoat it's a bit thin. To primer especially if you've had these dipped or any chemicals potential adhesion problems add a good dash of owatrol.
3. Undercoat on old work needs to be thick and to rapidly dry, build, then be easy to sand. If yours are indeed stripped and clean the stick with sandtex flexi undercoat if there old and chipped/cracked use coverstain as oits much thicker and dries in 2 hours. This is in essence filler paint.
4. Gloss I like sandtex they do a satin as well. Its pre mixed.ive been using dulux trade weathershield this week and whilst fine it's not as forgiving as sandtex. It's got lots of driers so skins in the tin an takes forever to mix completely being mixed in the shop. To thick and it wrinkles so it needs some owatrol and some white spirit. All oil based paints are needing black bristle brushes ideally or failing that Purdey monarch Pro extra. And a paintmate to keep them wet. Every few hours of painting rinse your brushes in white spirit otherwise they drag. Avoid plastic caulk and fillers esp on bottom edges.Use putty if you've got time(toupret can be painted in 6-8 days) gras a lacquer on small shallow fills. But undercoat your friend on old stuff.
Great information @johnnyb, really appreciate the time you and other have spend typing all this out.
I've seen the sprig guns for sale on Amazon, reasonably priced too.
Interesting to hear you use it regularly as other poster said to never use them 😂

It's all useful information though and what works for one may not work for another, I suppose I'll just have to find out by doing what works for me !
 
Zinsser AllCoat does seem to be the decorators favourite paint at the moment.

I don't like adding more options but if you do go down the oil based route Aluminium primer is worth looking at.

Even if you do use proper putty to point you can still use something like Timba Glaze to bed the glass in, it sticks the glass in nicely, glass just puttied in with no pins always makes me nervous.
Aluminum primer has also been recommended to me previously by Jim Sear who I mentioned earlier in the discussion
 
I think a sprig gun is great, I have a fletcher one. But it's probably only worth it if you are doing quite a few as they are not cheap, otherwise the fletcher push in ones are fine. Personally I find aluminium primer very "sticky" to paint with.
 
Ollies right I used blackfriars brand and it was super thick. Basically it's an additional layer then the finishing stuff goes on top. It us effective though.
 
I’m only used aluminium paint once, I painted ten windows (old, stripped to bare wood) with it then the usual undercoat and top coats, and ten without using it on my own house as an experiment. They were distributed so that there were equal amounts of each type facing each point of the compass. My conclusion was that the aluminium paint made no difference in longevity of the paint. They all need a repaint after circa eight years.
 
I think alkyd resin has that durability limit(or less) but ally primer blocks discolouration and resin stain. Which on the front doors I've used it on seems to hold true. Redwood can be dripping with resin. I'm assuming it works on hardwoods as well. Dud you find any help re bleeding and stains?
 
Thanks Robin, very happy to hear advice on spraying.
Interesting to hear you say that water based paints are the only realistic option for spraying. I haven't research in any detail but I though the Graco ultra max can spray oil based paints (the max model in particular). Perhaps its just that water based lends itself better to spraying?

Given the point you made regarding drying times, its another vote for using oil based paints this time of year.

I am currently spraying water based paint for the first time and quite like it for the safety aspect related to spraying.

Regarding drying time, the topcoat I am using is drying to touch dry anywhere between 45 minutes to about 1.5 hours depending upon how much heat I use from my space heating but at about 14 deg it will take maybe 1.5 hours and if I use the space heater maybe 45 minutes. If I used an additive the times would come down.

I am learning that paint manufacturers use additives to assist drying times and also add other qualities such as making the paint more flexible. You can often buy additives from the manufacturers to add to the paint which then adjusts the paint to suite the qualities you require such as faster drying times etc.

If you are going to use oil based paint this time of year I would check on the manufacturers recommended drying time along with temperature range and humidity.
 
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Great information @johnnyb, really appreciate the time you and other have spend typing all this out.
I've seen the sprig guns for sale on Amazon, reasonably priced too.
Interesting to hear you use it regularly as other poster said to never use them 😂

It's all useful information though and what works for one may not work for another, I suppose I'll just have to find out by doing what works for me !
A few years back I used to do a lot of slimline glazing and I used to get some guys in from a glazing firm, they used to bed the glazing on MS polymer, a silicone mastic. Then use traditional putty

I personally never use sprigs, on single glazing either bed on silicone or putty. If the glazing is done flat ie “on the bench”, once it’s in and face puttied it’s not gonna fall out.
 
Aluminium primer can be difficult to apply, of the ones I've used I found Dulux went on easiest.

It does need a lot of stirring before you use it and it can wreck brushes quite quickly.

I don't know if it gives better results than other options but it does seem to seal timber really well. I have a wooden fire surround which was constantly leaking sap from some knots (obviously not helped by the heat), I gave it a coat of Aluminium primer and never had a problem since.
 
A while back I carried out some building work on an old farmhouse. At some point in time, as it didn't have skirting in the hall , some bright spark had painted one on, with bitumen paint. o_O

It was easy enough to chip away the lime plaster top coat and affix skirting. but where it was painted on the riser of the bottom stair tread, it was much more problematic. Despite my best efforts at stripping it off, elements were still bleeding through. Thankfully, couple of coats of Aluminium Primer fixed the problem.(y)
 
So OP back here again.
So in the past weeks research on selecting a good exterior wood paint a particular brand of paint keeps getting mentioned that has not yet suggested here, that is Bedec MSP.
It seems a quite popular choice in sash window redecoration and has many devotees. HAs anyone here an opinion on it good or bad?

It water based, so not sure how winter weather may affect drying time, but it is certainly sprayable and that has become an important factor as sprayer purchase order has been approved by the financial controller!

Also, I have removed the box frames to access the condition of the cills, its apparent that 6 cills will be better off replaced than repaired.
The other 6 cills are in reasonably good condition, their overall profile edges are sound however they have areas where the surface is certainly not soft, but not as hard as it once was.
I feel they are far off need new sections spliced in but perhaps a coat of hardener would be useful.
Can anyone speak off using hardeners in this situation?
Would a coat 5* wood preserver be prudent seeing as the windows are entirely back to bare wood.
And do either of those treatments adversely affect, or otherwise, the Bedec MSP or other water based paint finishes?
 
Tikkurila otex adhesion primer then valti ultra topcoat.
Seconded. We used this system (although over a Teknos base primer that came on the then newish windows) in late 2016, still going strong, no sign of needing repainting yet and still looks great.
 
So OP back here again.
So in the past weeks research on selecting a good exterior wood paint a particular brand of paint keeps getting mentioned that has not yet suggested here, that is Bedec MSP.
It seems a quite popular choice in sash window redecoration and has many devotees. HAs anyone here an opinion on it good or bad?

It water based, so not sure how winter weather may affect drying time, but it is certainly sprayable and that has become an important factor as sprayer purchase order has been approved by the financial controller!

Also, I have removed the box frames to access the condition of the cills, its apparent that 6 cills will be better off replaced than repaired.
The other 6 cills are in reasonably good condition, their overall profile edges are sound however they have areas where the surface is certainly not soft, but not as hard as it once was.
I feel they are far off need new sections spliced in but perhaps a coat of hardener would be useful.
Can anyone speak off using hardeners in this situation?
Would a coat 5* wood preserver be prudent seeing as the windows are entirely back to bare wood.
And do either of those treatments adversely affect, or otherwise, the Bedec MSP or other water based paint finishes?
I have used sovereign solvent based wood preservative for years and it dries quickly and have never had a problem when overpainting it. So far in 40+ years I have not known anything rot after treating with sovereign wood preservative. If I make sash windows I would normally make a tray so I can submerge the lower part of the box window in the tray while I brush the preservative over the rest of the box. I do the same for the sashes then put sticks on top of the tray and stand the box sash on them so any surpulus drips back into the tray.

Regarding paint it does seem that: Tikkurila otex adhesion primer then valti ultra topcoat is popular. The top coat is supposed to be flexible and last between 8-12 years which is very good. I have used Santex in the past and generally obtain around 8 years before a re-coat is needed. But I might give the Tikkurila otex adhesion primer and valti ultra topcoat a try if I'm spraying or even brushing because it sounds very good.
 
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