Period Stud Walls

[malcolm]

What materials would be nice for stud walls? I need to build one as a new inner part of an exterior wall (see previous posts about timber frame completely eaten by a big fat beetle).

But I just don't like plasterboard. There is no plasterboard in the house where you can't tell is plasterboard. Cracks along the joins, soft and hollow etc.

My preference would be to use lath and lime plaster on the inside, but the lath alone was going to cost £180, and the equivalent area of plasterboard was £36. An alternative might be to use wood wool board in place of plasterboard and treat it like a solid wall when plastering.

 

[SilverSaloon]

you could double-board it, or put a layer of OSB board on 1st, then plasterboard ontop of that. this will prevent the hollow sound

or you can fill the void in the studwork by fitting solid insulation board like kingspan

 

[skier-hughes]

I chose lath and plaster, mostly because I thought I'd like the look of it and it may well add as much value to the house as it costs. I needed to insulate this very cold north wall, which is why I built the partition. Added sheepswool insulation behind. Another reason is, the wall would have been timber framed originally, so it's a better fit that plasterboard.
I am thought using plasterboard as the partition wall between the two rooms that this one large room is being split into. This allows me to run lots of electrical sockets into the room and gives me somewhere to hang heavy radiators from.

 

[malcolm]

That is a magnificent stud wall. It makes my 3 by 2 effort look lazy.

I'll maybe try some local timber merchants for lath as I'll need to plan some more downstairs in the winter. With VAT and delivery from the specialists it works out as expensive by length as 2 by 2 which doesn't seem fair when you need such a lot of it.

 

[skier-hughes]

I bought riven oak, but sawn oak is much cheaper, but not as good.
I also used a local timber merchant for the uprights. He supplied me with cut routed green oak, I trimmed it down to the size and shape I wanted and wedged the laths into the uprights. They made some sawn oak laths from some timber that wasn't up to scratch, so maybe worth investigating that option with your local timber yards.
Price isn't great I admit for the laths, but the green oak was amazingly cheap. It's really nice looking at it, still not plastered yet!! And the smell from the sheep's wool insulation is divine

 

[malcolm]

It's a lot nicer than my latest effort (an attic cupboard using the incredibly thick celotex required by building regs as a structural material). I'll look at planning ahead at some point and doing something nice.

 

[Cocoa]

How about reed mat? I got some from Ty Mawr for the last lot of plastering I did, and it worked well and worked out a lot more cheaply than lathes!

 

[malcolm]

Thanks for mentioning Ty Mawr. I've had a good look at their products. For most of what I'm doing (adding interior wall insulation for building regs) thickness is important. I've lost 5 inches from the depth of the wardrobes as I wanted an inch or two air gap to the external timber frame. Ought to be OK as other half is on a diet and will presumably be filling the wardrobe with narrower clothes.

I really don't like plasterboard. It's messy to cut, fills the house with dust that will kill a Dyson, difficult to fit to oddly shaped walls, wasteful, and the fillers they give you are mostly water so they shrink and crack, but they chemically set quickly so don't allow the time for compressing later on like lime. But I did use plasterboard.

I think I'll go for lath or reed next time and I don't think it will take any longer (other than the drying time). Is the reed mat OK for stud walls?

I've noticed the older stud walls in the house are built from much more substantial timber than 3 by 2. I think a lot of the hollowness from plasterboard is due to the insubstantial frame.

 

[Cocoa]

Well, I have used reed matt in two places so far: against a new stud wall with Kingspan behind it in 3 little alcoves, and against wood lintels over the windows. The house was originally an end of terrace, and then 100 years into its life another building was built next door, which 'borrowed; the existing external wall. On each floor, however, front and back, there are alcoves where the wall is only single skin, and despite being fairly chunky stone, too much noise comes through. Hence the stud, and the Kingspan - so the reed matt is supported by the rigid insulation directly behind it. I used haired lime plaster, but it seemed to really only need one coat, and then a skim on top.

Around the windows, the plaster had fallen off the wood lintels - I guess there was insufficient key. I experimented with hammering pieces of lathe onto it, and also large headed nails (this was recommended somewhere - can't remember where I read it!) Both were fiddly and time consuming, and I struggled to adequately support the plaster in the gap behind the lintel and the exterior wall, which let in an absolute gale. Reed matt solved the problem, but again it was supported by something fairly rigid behind it. For what it's worth, I plan to use reed matt and hemp plaster for a stud wall I need to re-do (I'm gearing myself up to knock down the existing plasterboard next week!) and I think reed will do the job fine. It's a bit like a bundle of twigs - you could snap each of them individually, but not to whole bundle together.

On another note, I had to replace plaster that had fallen off the lathes in the stairwell. The lathes used in a high traffic area were insufficient - I don't know when they were put in, but quite a few were not much thicker than a piece of strip wood, and as a result a number had broken, or there was simply too much give and the old plaster eventually cracked and fell off.

Lime is good stuff, isn't it? I have one summer's worth of plastering under my belt, and I have found it very forgiving! My earliest efforts are noticably less even than the later ones, but I still think it looks pretty good for a novice! Bits I struggle with are exterior corners and getting a smooth finish to the final skim....

 

[malcolm]

Thanks for that. In return I can't help with outside corners as I haven't attempted one yet, but for a smooth finish I tend to wait until the lime (mixed with fine plastering sand) has dried hard enough so it can't be pressed by a float, then use a plastic float with a rough face (possibly called cross grain floats) and use it like sand paper to take the top off the high bits and move the lime to the low bits. A bit of water spray and a final float to press the lime in, then a rub over with a damp sponge to fill in those little bits that are left. That leaves the walls flat enough to take a paint finish.

The sponge is also useful on the modern fillers, but because they don't contain any sand it will tend to leave marks.

 

[Zebra]

You mentioned you might use woodwool board. I've used this lots, but not where there is a hollow space behind. I think it is a little to insubstantial for that - at least the 15mm is, the 25mm thick would be OK I believe. Or you could board with 13mm OSB first and then the woodwool, this is what I've done on one of my ceilings. A confession too - even though Ty Mawr said that you ought to do two coats of lime plaster over woodwool boards, I've only done one.........

 

[bennoa1]

I've used the woodwool boards on a stud frame but 25mm. I've used some 15mm to box in some cables in the bedroom which feed into the extension lost so can access in the future but this will be lost behind the plaster and is only 8" wide and 3 foot high. The 25mm is pretty rigid and worked well on the 2 outside walls with lambswool insulation behind. Stainless screws to attach using the spacer washers, or SS penny washers where I didn't have as much space. I then used the hemp plaster which I put a thick coat of coarse on first and then a fine coat to finish as the course was too course. Clay paint to finish and it looks great. On the outer edges I rounded the edge which looks great around the window and at the top of the wall where it cuts back into the oak wall plate, which we cleaned up and waxed. This was in the bathroom and our first attempt at any of this as we wanted to be happy with something that worked and looked good we could use in other rooms.

 

[Zebra]

Sounds fantastic!

 

[malcolm]

That does sound nice.

Wood wool boards direct to the brick with lime plaster could be a possibility for the living area where there is a cavity wall where I don't want to fill the cavity and an internal wall at a heating boundary. Does it bend neatly? I have a curve in one of the walls. I would need 80mm thickness for building regs but it could be made up from thinner layers. Would you use a vapour barrier behind it? My feeling is not so If I get any damp it might alert me by appearing on the inside of the wall.

I think the kitchen will have to be stud wall to support the cupboards. I've still not sorted out the damp wall. The gutter and ground levels are fixed but the leading, window, pointing and drains are in progress. I don't think the wall will dry before the kitchen is installed so maybe a free standing stud wall with a ventilated cavity and the odd brace back to the brickwork.

I insulated the loft above the shower room recently. Probably no coincidence that the top of an internal wall in the shower room has very quickly become mouldy. I'm going to have to be very careful with water vapour and extraction with all this insulation.

 

[Zebra]

No it doesn't bend.

 

[malcolm]

I have a small job plastering and rendering around our new oriel window (photo below). There are three leaded lights and the rest of the holes need to be rendered.

Woodwool board would be perfect but I can't find anyone who will post woodwool board (50mm thick) for less than £100, and it doesn't seem to be available locally. Can anyone suggest a breathable alternative for a small job?

This time I'm going to use lath and lime plaster on the inside having found a supplier on eBay who sells sawn oak for 50p/m and reasonable postage. Most of the panels don't need to be insulated so I could use lath as a base for the render and stuff loft insulation into the panels that need insulation.

 

[livias]

Zillions of woodwool board is heading this way. Do you want to add to the order?

 

[livias]

Lovely window. I shall have to pop round for a good look

 

[malcolm]

That would be fantastic. I'll add up what we are likely to need and send a private message.

Do pop around. I'm here most of the time. All of the planned work is finished enough to allow the scaffolding to be removed - the roof, paint stripping and pointing are finished. Just the unplanned stuff to do now. Front should be ready for paint by the time the linseed paint arrives, so only really the gable left to do.