A Question of Stairs

[Flyfisher]

We have an old staircase that I'm preparing for painting. It's actually quite roughly built and has also suffered from some historical water damage, all of which has left it with quite large gaps at the edges of the treads. The current plan is to eventually fit a stair carpet fixed with stair rods, so the edges of the staircase will be exposed and visible.

I have considered taking the treads and risers apart, cutting new straight edges and fixing new wood to make all the joints properly square and tight fitting, but my feeling is that this would be rather too 'invasive' and would alter the character of the staircase too much (quite apart from possibly requiring LBC, I'm not really sure), so I've decided against that.

So I've decided to simply fill the gaps prior to painting and my question is what would be the best sort of filler to use?

I think it needs to be flexible enough to allow for the slight movement of the stair treads, but not so flexible that it cannot be painted without the finish flaking, or should I not worry about flexibility and use some sort of two-part solid filler, which might be better for a painted finish?

What does the panel think?

The gaps are up to 5mm in some places but mostly about 2-3mm. These photos should give an idea of the problem.

 

[DJH]

My first thoughts FF are a good quality painters caulk or a polysulphide type mastic... I've had success with both. Firstly though if there is any movement at all in the treads it would be worth sticking or pinning some blocks beneath those that are flexing and even those that aren't, just in case.

Doug

 

[JoceAndChris]

Lovely staircase - I'm no expert but I'd probably just use a linseed oil based wood filler on the 2mm and 3mm gaps and then make wooden splines to fill the 5mm ones- a lot of messing about but it would improve the overall look if you plan to paint the whole thing.

Have you looked at the lovely, lovely Roger Oates runners?

http://www.rogeroates.com/products/runners/red/

 

[Nigel Watts]

When I faced a similar issue I used papier mache, with some added linseed oil. Ten years later it is holding up quite well.

 

[88v8]

See what you mean about quite roughly built, appears the treads & risers not recessed into the string? Always going to be some movement. Might help if you can bracket them together in some better way from beneath, even if it's just metal angle brackets.
I'd forgotten about papier mache as a filler, used that between floorboards years ago but moved house before ascertaining the longevity. Worth a try. Otherwise perhaps some of that acrylic decorator's filler, which is overpaintable, reasonably flexible and has the merit of being easy to remove.
Wouldn't use the two-part, it's a pig to remove when eventually it cracks.

Ivor

 

[Flyfisher]

Thanks for the suggestions. I've already added some additional support and wedges underneath and this has dramatically reduced any movement, though my feeling is that some sort of flexible filler would be best as I doubt I've totally eliminated movement. I don't think that would be possible without some serious work, or even redesign, which is hardly in the spirit of things.

I suppose I could have just opted for a fully fitted carpet, which would cover the cracks, but where's the fun in taking the easy option? :wink:

I'm glad of Ivor's advice against a two-part filler, it didn't really feel like the right thing. I hadn't thought of papier mache though - would it be smooth enough for a painted finish?

I've got some linseed putty and wondered about using that, but perhaps it wouldn't be flexible enough and would crack in time?

I'm leaning towards some sort of decorators caulking . . .

Meanwhile, Joce, as usual, has come up with some stunning ideas for the finished product. Fortunately I was sitting down when I read the price list. :wink: I thought the structural works were expensive enough but now we're starting to think seriously about the decoration phase, I'm not so sure!

 

[88v8]

It's gonna crack, it's what painted staircases do. Like painted panelling, painted doors, just think of it as patina.
Another alternative - don't fill it, just work the paint well into the gap so you don't see bare wood. If necessary, to prevent the paint bridging the gap, paint one side with a bit of card in place to stop paint getting on the other side, then the next day do the other side with the card protecting the side you already painted.

My recollection of papier mache is it needed a lot of sanding, but that could just have been the way I mixed it. Linseed putty, old school, eventually will come adrift, sooner of course where you can't prime the wood.

Ivor

 

[tobydog]

Another alternative - don't fill it, just work the paint well into the gap so you don't see bare wood.
Ivor

Totally agree but caulking would be my second choice. Do you really want it to look perfect? If you were to sand and prime the whole thing first, you will get a very good idea of what the finished project will look like anyway. If you then decide to caulk or fill then you should have a bond with the primer.

 

[Flyfisher]

It's gonna crack, it's what painted staircases do.

Yes, I suspect thats the truth of the matter, hence my leaning towards a flexible decorators caulk.

Interesting suggestion to not bother filling the gaps at all. They are currently very visible because of the state of the staircase and the fact that most of the gaps have opened up between unpainted wood. Working paint into the gaps would make them a lot less noticeable and I'd still have the option to fill them before the final coat anyway.

I think that might be the way forward. Thanks.

 

[plasticpigeon]

I've tried caulk, both cheap and dulux stuff, and it doesn't fill big gaps as it shrinks too much. 1mm gaps would be ok but not bigger. I think if you bunged up the gap with something, be it epoxy wood filler, paper mache, slips of wood or putty, caulk could go over the top to form a thin flexible paintable layer, but I've had no success filling gaps like that with caulk.

 

[angrybird]

I've tried to fill gaps with flexible caulk on painted paneling, looked fine for about a month and then it started to crack now i'm really stuck what to do next

 

[Lime]

There is nothing that will fill the gaps and last more than a very short while.
The everyday expansion and contraction and movement when walked on will soon open up most cracks such as shown.
In this instance, instead of paint or carpet right up to the edge, I'd strip the wood and varnish it.
Cracks in varnished wood are a lot less obvious compared to those in a painted surface.

 

[Toby Newell]

Polyester resin (two part filler) will likely crack but is the quickest method of filling. Going over the top with the best quality caulk you can find will hold the two part filler in place when it cracks.

Alternatively wood slithers may be a better, but much more time consuming bet. Any resulting smaller gaps can be filled with sawdust and a flexible filler resin like Lecol 7500.

I think the gaps would look much better filled, but it's a personal preference.

Fixing the treads as firmly as possible and refixing wedges to the underside as has been said, will only partially ameliorate the movement, unless of course you fit a stair lift or develop the ability of levitation.