Skirting issues help

[deema]

I’m hoping that someone has a cunning solution to a problem I have. Just over a year ago, I remodelled a house I had bought, as part of it all the skirting and architraves were replaced. The skirting and architrave is MRMDF, and there is an awful lot of it. I had it installed and the house painted, that’s not blaming the chaps who did it, but I know some of the way it was installed wasn’t brilliant. Anyway, it’s in, it’s painted and carpets are all down. After a year, the underfloor heating keeping the house at a constant temperature everything has dried out and shrunk and might still be moving ….so far by 2 ~3 mm or c 1/16”. I had a load of cabinets made which were beautifully scribed and fitted to the walls, again made of MRMDF, painted. A similar size gap has appeared all around them to the walls / ceilings. Now, the cabinets I can simply re-caulk. Very irritating, time consuming with repaint the walls / ceilings. The skirtings however….well. I can’t think of a solution without ripping it out and a redo, and then I can’t guarantee it wont happen again. So I’d like a solution that doesn’t involve removing it. It’s amazing how rough it looks in the photo. In reality the finish isn’t too bad……I did a quick caulk to see what would happen after about 6 months ago, only rough……it expanded beyond the elastic limit of the caulk.

So, the skirting joints had been glued, but, clearly when something shrinks something has to give. The skirting was glued and pinned to the walls.

 

[Ollie78]

Those painters should be thoroughly ashamed of themselves.

There is one filler I like for this sort of thing called toupret tx 110. It is a powder filler they sell it in toolstation. Sands very easily and sets quick.
Hook out the caulk or whatever is in there now as best you can.
Mix up the filler fairly thick but thoroughly. Fill it, wait, sand it, paint it.

It is the least likely to crack of any filler I have tried and that is a pretty long list.

 

[Blackswanwood]

If I’ve understood correctly you have tried a caulk fix on the skirting but it’s then shrunk again.

It must reach a point where it stops shrinking? I’d be inclined to have another go at caulking it.

 

[HOJ]

Seems odd its shrinking length ways and being MDF, is the building moving a bit.

I can't really tell from the piccy, is it just a butt joint? when I have to make a joint in a run I make a long scarf joint overlap with more gluing faces, and can be feathered out better.

 

[Bingy man]

I can only assume the mrmdf was wet when installed or there was a high moisture content in the rooms or both. As above it at some point should stabilise and filling should take care of it . As per @Ollie78 toupret filler is excellent at gap filling, easy to sand . On a second note are the cracks in one room ? Is there any chance of a water leak in the vicinity? . It could be worth lifting the carpet and check for damp patches maybe use a moisture meter…

Edit is it my eyes or a shadow but there seems to be a water stain or patch circled in the pic .

 

[JSW]

Edit is it my eyes or a shadow but there seems to be a water stain or patch circled in the pic .

Certainly looks to have blown the face of the MDF, slight bulging to the top of the moulding also. If the joint ends weren't sealed, they may have taken in moisture.

 

[Howie65]

Hi,

You need to use a filler that isn't water based, something like Ronseal(green tin) that is a resin type like car body filler, with the 2 parts to mix together, also available from Toolstation although a bit more money and it sands very easily.

Also, today's water based paints don't help, so stay old school when painting MDF of any kind.

 

[Bingy man]

Certainly looks to have blown the face of the MDF, slight bulging to the top of the moulding also. If the joint ends weren't sealed, they may have taken in moisture.

Last time I saw that mark I had fitted new skirts and ran out - I found an off cut that had been outside in the rain but most of it was under a sheet - when I saw it the following morning it was duly ripped out and replace with a new piece ..

 

[ChaiLatte]

To me, the one that has been caulked looks to have failed because the caulk was too shallowly applied (or applied as deeply as was possible at the time it was applied). It has acted like the skin of a balloon and split.

If it were possible to put a needle tip on a caulk gun (or perhaps to put some caulk into a syringe), you can start at the back of the crack and completely fill it - perhaps rake out the gap with a hacksaw or multitool blade first.

The challenge with the any of the filler ideas is that filler is solid - it will not expand if the crack widens and will not compress if the crack becomes smaller.

Silicone sealers are sold in high modulus and low modulus, to accommodate more or less movement. If you could find a non-silicone (paintable) sealant of the appropriate modulus, that would be the best, but it might take some effort to locate the right product.

 

[deema]

The skirting joints joints are mitred / scarfed. The house is dry, no leaks, no damp, no adverse humidity. The MRMDF was bought pre painted and wasn’t left outside. The rooms are either 18 or 20C at all times. The house is c80 years old double skinned, and now fully insulated, floors, walls roof. It has dried out c2 years prior to it being gutted before we refurbished the inside.

The only thing that I can think that may have caused a problem is the screed drying out over the UFH that we installed throughout.

I’m guilty of the carp caulking, the gap was about the width of a sheet of paper when applied.