Decorating advice required

[cracatilla]

I've just had some work done on the house and have new bare plaster to paint.
Should you 'seal' it with PVA before you paint it?
Or is the Mrs Dad full of it
Cheers

 

[Lonebudman]

Yep you should pva it.
Just dilute it down with water and apply it with whats easiest for you,I use a big sponge usually.
If you don't do it prepare yourself for a nightmare lol.

 

[cracatilla]

What sort of ratio?

 

[Lonebudman]

Prolly 5 part water to pva ratio but make sure the plaster is 100% dry before you apply it.You don't want it too thick or it will show when you paint it,fairly watery.
Some people prefer to use watered down paint instead at a 3 part paint to water ratio,you'll just need a few coats of it before normal painting.

 

[Richard_H]

Yeah you're wasting your time if you don't because your first coat will just sink into the plaster. Thin pva, takes minutes (I roller it on) wait for it to dry and then off you go.

 

[walkie]

Your father in law is spot on. Watered down PVA (ratio already stated above) paint on sparingly and allow to dry.

This will seal the new plaster perfectly.

 

[db94]

Decorating advice - put it off, do something else instead. Being doing my bathroom all week and it's gobbled up all my free time (forum time) Decorating is always better if you do it "next week"

 

[.Q.]

I'm a painter and decorator. Do not put pva on plaster, ever. New plaster takes about a week to dry, but several months to fully cure. Wait a week or two at least, a dehumidifyer will speed up the process. When ready to go, apply a lightly watered (5% extra water, a small cupful or less will suffice) first coat, it's supposed to drink in to mesh with the substate, applying pva doesn't allow paint to bond with the plaster and will only cause the paint to form a skin and can be prone to failure / lifting.

When dry, apply any fillers or caulking needed (levelling with a wet filling knife), then when ready for next coat, put on thinly (called a 'mist' coat). When dry, lightly abrade any imperfections then put on a finishing coat.

Top tips - buy good quality rollers and brushes e.g. Purdy brushes are the pros choice and with care will last years.
Don't buy cheap paint, it's inferior in coverage and durability, use either Dulux or Johnstones vinyl matt. Or use vinyl silk for bathrooms.
A few quality sundries can last for many years and are a great investment such as cotton twill dustsheets, quality scraper and filling knives, button release extension pole, paint kettle + skuttle (not trays).

If you need to seal poor surfaces, try Zinsser 123, sticks like hell to most things. Try your local trade paint store, they will be happy for your business, will give good advice and many will give a discout to local residents, or set up a cash accout for free. The money saved will mean your good quality materials will cost about the same as poor stuff from BnQ.

Hope some of this is of use, feel free to ask away if I can be of further assistance.

 

[Lonebudman]

The age old pva or not argument!

I've used both methods and both work fine for me and that includes repainting at a much later date.
Basically if the plaster is still damp small bubbles can appear in the paint and also when repainting the pva can be reactivated.
Times have changed and paint is better,IIRC correctly some paint manufacturers now advise to pva before using emulsion and if vinyl paints are to be used definitely don't pva first.
As I say i've had no issue using pva as long as it is well watered down,I can see problems arising if the pva is applied thickly.

Q is correct though if you wish to conform to British Standards but this is mostly to do with the new plaster retaining moisture,leave it 2 weeks at least before painting.

Anyways Q,fancy giving me some varnish advice?

 

[.Q.]

I have used pva as a bonding solution to very friable surfaces, but only thinly then with Zinseer 123 or another 'super' primer on top, prior to decorative finshes. Best practice to prepare existing paintwork is to wash with sugar soap. It provides a chemically consistent surface as well as de-greasing and will etch the surface (at a microscopic level) so paint with adhere completely soundly.

The key to varnishing (or any polished finish, e.g. gloss), is to have all filling, sanding, or any other making good complete before applying the last coat. Several thin coats are always better than one thick or overapplied coat and you can refine the finish between coats. Use a tack cloth (sticky rags, easily found in any DIY or paint store) to remove imperfections before applying your finish. Use coloured wood filler, matching as closely as possible to the natural wood, and cover-up crayons or pens can hide flaws. Experiment with matching the wood grain over anything that will show through the varnish that you do not wish to see.

With natural wood finishing, you can always go darker, but not lighter. Varnish with a sublte tint can help camoflage blemishes, or help to match if a variety of woods have been used. The job I'm on at the moment has velux and sliding windows + sills, staircase and skirting boards all made of different woods, a tinted matt woodstain goes a long way to making it appear as if they are all consistent with each other.

I always target buy what I need rather than buying large amounts of something. Especially for gloss and varnish where a polished, mirror finish is required. Buy paint kettles to decant into, don't work out of a tin as it will start to oxidize, reducing 'open time', the time you have to work or lay off gloss or varnish. When your task is complete, either dispose of the used varnish or recant into another container. Keep your gear clean and free of bits, ready for next use, safe in the knowledge it is uncomtaminated! Like my gloss use, I have an 'A' and a 'B' tin, A is new, clean paint, B has been recanted so would need passing through muslin to ensure a top quality finish.

I'll shut up now as I've prattled on like a loony, gibber.

 

[Lonebudman]

Fantastic advice there Q and confirms I have the correct technique though I gave up trying to match wood filler a long time ago and prefer to use fine sawdust of the wood i'm using mixed with as little neat pva as possible.Its not perfect but I find its much closer than off the shelf filler.I usually keep a bag for future use.Not a luxury you have though if you're not fitting it.

Woodstain as you say is great for blending different wood together.I usually use it on doorframes as they aren't as handy to replace as architrave,doorstop etc and woodstain does a suprisingly good job of blending the doorframe to the timber i'm using.

I usually work out of the tin though so i'll have to check out these paint kettles!

I did have a specfic question though.I fitted white oak skirting board a few years ago and used clear satin varnish but i've been rather dismayed how quick the varnish yellows detracting from the oaks natural colour.
Will this happen no matter what varnish I use or should I use an alternative like wax or something similar?
I recently tiled the kitchen floor so as the skirting is up i've sanded the old varnish off and prepped it ready for whatever I decide to do.

Thanks for going out of your way Q,it's much appreciated. 8)

 

[JuniorChubb]

Leave it as bare plaster mate, go for that Tatooine look...

It will save time and be cheaper :wink:

 

[x-pack]

Nah **** that. PVA it.

My brother plastered a wall for me 12 months ago. PVA'd over it when dry and the wall is perfect.


...you haven't really got a straight answer on this thread have you? :?

 

[.Q.]

The straight answer is Do Not PVA plaster! :lol:
It might seem ok, but it will create a barrier, meaning the paint forms a film, as opposed to the first (lightly watered) coat drinking in and subsequent coats bonding to that, thus meshing with the plaster. Frescoes survive centuries, and they did not pva thier walls! :lol: No idea how this PVA on walls started but it's prevalent and a total myth and something of a running joke amoungst decorators. Put simply, it's a really bad idea, don't do it!

I find it odd how people think nothing of spending a fortune on other aspects of thier home and then will scrimp every last penny in regards the decorating. Professional, qualified decorating will increase the value and quality of a property massively. Unfortunatey there's many a useless painter out there with no talent for the work, and with no formal training, just chucking paint around with no proper preparation work or care. Good decorators have a motto - fail to prepare, then prepare to fail.

Lonebudman, when varnishing skirting board, if there's any gapping, I first pipe in coloured wood filler (close match or a shade lighter), the type for a cartridge gun, to where the skirting meets the wall. This will aborb the varish / woodstain and match seamlessly. Sand lightly when dry, also punching in any proud nails and filling them. As you've sanded them, you could use a woodstain, either clear or with a subtle tint. Either that or polyurethane varnish, should be hard as nails. You have a choice, as you prefer, for sheen level from matt woodstain to glossy finish.

Quick tip - always start any decoarting task at the most awkward or hard to reach area first and work out from there. Again, good quality brushes will be the best labour-saving tool, with superior pick-up, distribution and accuracy. When applying caulk or filler to corners, have a paint kettle of water and a damp rag to smooth out the caulk as you go, or use a thin filling knife to create really sharp corners. I use a plasterer's spoon (looks like a tiny pointing trowel) as a sculpting tool for filler.

Sorry to waffle, hope some of this is of use. See y'all next time for more Dave's decorating digest!

 

[Lonebudman]

To answer my question basically the varnish will yellow with age no matter what?

No way will any woodstain touch my white oak(blasphemy),ever!
As I said in my post I make my own filler,off the shelf filler rarely matches.
Must be nice to work in properties where you can use nails for skirting board,older properties with less than perfect walls using screws are the answer.Using screws you will always have more purchase to pull the board to wall enabling you get rid of gaps better.Not all properties have perfect walls.
I prefer to use caulk to fill gaps to the wall as its paintable and blends in with the wall when painted,you then retain the lines of the skirting board.
If you do your joinery correctly you shouldn't really need filler except for filling nail/screw holes.
I haven't used a painter/decorater in years and any properties i've prepared over the years have sold quickly.

Thanks again Q. 8)

 

[dinner squadron 2]

I usually use a watered down paint, some cheap gear from b&q. You might need 2 coats of it before you apply your finished colour and its more work but your finish is far better. Just dont spend big and buy dulux 1 coat, it still takes a couple of coats and just wastes your money

 

[x-pack]

PVA is the way :lol: My perfect wall speaks for itself

 

[.Q.]

All I can do is give my professional advice. Covering walls in slimy glue is a daft idea. :roll:

Lonebudman, sounds like you've got it sussed mate. Sun damage will cause many things to yellow, including varnish, it's unavoidable. You can get clear / colourless wood finishes such as Osmo Oil.
My point about using woodfiller instead of caulk is to a skirting where a natural wood finish is required, is that it will blend seemlessly with the skirting. Caulk for when skirting / architrave is painted.
Most of my work is renovating old properties, such as the 16th century cottage I'm on at the moment. Not a straight wall in sight!

Here's a quick snap of part of a project from last year, featuring painted frames out from the window reveals and a Corbusier staircase. Saucy.

 

[Lonebudman]

Don't get how wood filler can be a natural finish,guess its down to preference anyways,I prefer the to keep the line of the skirting board I guess.

That room looks splendid! 8)

You can get clear / colourless wood finishes such as Osmo Oil.

Will this still yellow?

Thanks again Q.

 

[.Q.]

Thanks mate, and you're very welcome. This room was a nightmare, the beams were all varnished and the customer wanted them painted. Blitz with the sander then fire on Zinsser BIN to seal them. The steps lead to a mezzanine, so it's a huge double height room up to the apex. I was eating Farrow + Ball for weeks!

No idea if other wood finishes will yellow as varnish does, but I've never experienced any discolouration issues with Omso oil or Sikkens wood finishes. They give a lovely finish and are a pleasure to use.
Wood filler will soak up varnish etc. blending naturally where as caulk won't. Personal preference and a minor touch.