Advice fitting skirting to non fully plastered walls

Hey guys. Hope you're all doing well. I would like your opinions/thoughts on my plans on installing skirting in one of our rooms.

I had to get my front living room treated for dry rot, and I tell you what, it wasn't good for my epilepsy and depression. Anyway, I'm digressing here a bit.

Rather than get a carpenter to fit the skirting, I would like to do it myself and save a few quid. Plus it would be good to increase my DIY knowledge/skills.

The walls have been replastered, but not to floor level (https://www.dropbox.com/s/zt4oc1ltogwlzga/20161218_174052.jpg?dl=0). The plaster finishes about 100mm above floor level as this is where the treating company put in new DPC using PVC injection; it was found the joists under the bay window were saturated due to the issue.

I have been told I can't use fixings as this would lead to the chemicals they had used leaching out and corroding the fixings etc.

So what I am planning on doing is using ogee skirting (http://www.emafyl.com/index.php?route=product/product&product_id=1044&search=Skirting) made from polystyrene material and attach it using expanding foam adhesive such as insta stik. I'm using this type of skirting for the following reasons:

1. If we are unlucky and the dry rot returns, the the skirting will not get affected;
2. Because a part of the skirting is below DPC level, it will need to be moisture resistant. The alternative could have been to get wooden skirting but then I would have to apply a waterproof coat to the back before installing it, meaning more time/labour.

I think this is feasible as the plaster is about 8-10mm thick. The only problem I can foresee is cutting the skirting as this type of material is susceptible to melting when cut with a mechanical saw.

What do you guys think? Thanks in advance guys. Much appreciated.

Luqmam Ahmed, good evening.

A few things or so?

1/. The gap between plaster finish and floor is fairly large, if you do use an adhesive [not uncommon] you will possibly have an issue where the unsupported area of Skirting left in the gap between plaster and brick could tend to allow the skirting to deform into the space where the plaster is missing especially is someone taps [kicks] the skirting and it moves back because there is no plaster taken down to floor level.

2/. In the digital image posted, there appears to be the internal part of an air brick? if indeed the gap or space is an air brick then cold air from the external WILL get in behind the new skirting? it WILL cause condensation to form on the inner surface of the new Skirting, and indeed a cold area along the length of the new Skirting.

3/. If you use your intended polystyrene skirting, two things? A/. it is very flexible compared with timber, see 1/. above. + this material can and is susceptible to being melted by some adhesives??

How about? you fix a treated timber strip at floor level, glued to the brickwork, the timber will not rot, but the strip will provide much needed support to the Skirting at floor level?

You really need to do something about the air brick that is protruding above floor level, at least the air brick hole needs to be blocked of above floor level?

As for the material of the Skirting itself? it may be possible to pick up treated Skirting? just a thought.

Ken.

KenGMac said:

1/. The gap between plaster finish and floor is fairly large, if you do use an adhesive [not uncommon] you will possibly have an issue where the unsupported area of Skirting left in the gap between plaster and brick could tend to allow the skirting to deform into the space where the plaster is missing especially is someone taps [kicks] the skirting and it moves back because there is no plaster taken down to floor level.

Click to expand...

The expanding foam will fill the gap.

Put something very heavy against the skirting to jam it against the wall as the glue sets, or nail some temporary bracing battens to the floor, otherwise the foam will expand and force the skirting away from the wall.

Thanks guys for your much needed advice/responses.

You are right in assuming those are air bricks. Those were newly put in by the company to increase sub floor ventilation. However I'm worried now that I might inadvertently totally block the air bricks, but you're right, the above floor portions of them need to be blanked off internally.

Would it be possible to use expanding foam filler? It's waterproof (I think) but the only concern I have is that it will slump and might accidentally fill the whole air brick, unless I build it up in layers? Or may be I should put in some kind of horizontal blanking material to support the foam filler whilst it sets?

Or am I over complicating things?

Put a bit of polythene over the brick, glue the skirting, then once dry pull the polythene out. I would squirt the foam either side of the brick a but not directly over it, so the middle section of skirting is not actually glued. You can always poke something through the holes from outside to clear them if they get blocked.

Thanks a lot guys for your help. But now it's got me wondering why the company put the DPC at such a high level. A bit odd.

Luqmam Ahmed said:

But now it's got me wondering why the company put the DPC at such a high level. A bit odd.

Click to expand...

Can you tell where they injected it?

Yeah I took photographic records of the work. It's literally where the plaster stops.

Here's a photo just after they did the injection:

https://www.dropbox.com/s/ltcf7s7ic9yf4c4/20161011_143113.jpg?dl=0

So how did they propose this would help your joists?

They wrapped the joist ends in moisture resistant membrane but also said a new DPC is required to prevent rising damp.

Please don't say I've been done over by these guys. They were going to charge me an extortionate price but I managed to knock 30% off.

If it didn't have a rising (capillary) damp problem before then it didn't need a DPC to fix the nonexistent problem. Or maybe it did have some capillary damp? Either way the DPC wont hurt. Wrapping the joists was the important bit.

It definitely had some issues. A the joist ends at the bay window were saturated/damp and the floor at that end was receding too. There was evidence it was an ongoing issue as there was evidence the joists at that section had been replaced, so they weren't continuous/one length joists.

Defo needed fixing.

Luqmam Ahmed said:

A the joist ends at the bay window were saturated/damp and the floor at that end was receding too.

Click to expand...

Yes, but that would have been penetrating damp, not rising damp. My house had exactly the same issue because the joists are below outside ground level.

My joist levels are low in relation to the ground level. They're only about one brick course above GL.

So may be because of splash back during rain there was penetrating damp?

You won't believe the weird stuff the previous owners had done to the house. My biggest regret was not getting a proper survey done.