100mm Insulated Drylining: how do you mount kitchen units, Rads, Curtain poles etc.,

ReadySteadyGo

Hi,

My home is made from old fashioned cavity block. I have stripped the inside of the external walls back to the cavity block. I am planning on using the SEI grant to put up about 100mm of insulation and board.

I don't know exact mounting heights and locations for kitchen units, rads, Toilet suite.

Electrical conduit and some plumbing pipework will run along some of the walls.

How would you suggest to mount the insulated drylining?

Cut the back off some board and put in some wood to mount the heavy units on (so the fixings would be smaller) ?
Buy 150mm screws and plugs?
Cut the back of the board to allow pipes to run in it?

I talked to a kingspan rep, who said the boards he would recommend are foil backed (k-18 and tw-56), and should under no circumstances be cut. His suggestion was to put a strip of thick timber flush with the plasterboard, and run the insulate board up to this on each side. and to build out a service batton for the pipes.

I will lose more room space doing this, and I will need to know exactly where my kitchen units and rads are going before I can put the timber. And it does not address curtain poles, Mirrors, Flatscreen TV's etc.,

Thanks,

Sean.

bbam

Ask for "Frame fixers" in your local builders providers... that's what we used and they are rock solid, right through everything into the concrete...

like this...
http://www.wickes.co.uk/Frame-Fixers/invt/515502

jack of all

It's a big problem with drylining; the preferred solution is a solid "grounds" (timber, mdf or plywood) as you already indicate. Frame anchors are strong but with heavy kitchen units etc you are still going to have problems with the shear load and the fact that you'll only have 50- 75mm embedment in the actual load bearing concrete AND if your walls are only hollow block you've only got maybe 30- 40mm of concrete to bite into. For medium weight items standard fixings for drywall are fine (I use Rayfix Gold). Fischer fixings do some great nylon fixings for use with hollow block.

Creating a service zone for wiring and plumbing is a must- if you starting hacking away at the insulant you'll reduce its effectiveness; the use of a service zone allows you to consider airtightness (you should look into this if going to all this effort) and gives you great freedom with planning your services runs and locations etc.

Hope this helps.

Buford T Justice

jack of all wrote: »

For medium weight items standard fixings for drywall are fine (I use Rayfix Gold). Fischer fixings do some great nylon fixings for use with hollow block.

Unless you are hanging pictures, I wouldn't use these fixings, they are rubbish. The weight of curtains will pull them out of the wall, and consider fixing a shelf to the wall. Over time things will naturally get left on it, adding and adding to the weight. Before you know it these fixings will pull out of the wall to. They're rubbish imo. I'd be going straight into the block in all cases if possible

antiskeptic

ReadySteadyGo wrote: »

How would you suggest to mount the insulated drylining? Cut the back off some board and put in some wood to mount the heavy units on (so the fixings would be smaller) ?

I will lose more room space doing this, and I will need to know exactly where my kitchen units and rads are going before I can put the timber. And it does not address curtain poles, Mirrors, Flatscreen TV's etc

Consider building up the 100mm insulation in two layers. Firstly a layer of unbroken insulation attached to the wall (say 80mm thick). Then fix insulated (20mm thick insulation) plasterboard on top of that (using mushroom fixings though to the cavity block). Before you put up the insulated board though, glue a 20mm thick batten to the first layer of insulation in the places where reinforcment is needed. Cut a corresponding cavity out of the board insulation (if you're careful with your measurements you can do this quite neatly with out loosing insulation effect - wood is an insulator too). When its time fix kitchen units/rads etc. you'll effectively be gripping the plasterboard between unit/rad and batten - the plasterboard is plenty strong once you've distributed the load in this way.

It can't be too difficult to figure out height lines for units/rad/curtain pole mouting points. If you like, install over-long battens so as to provide scope for some lateral re-positioning come actual finishing.

Pipe/electric runs can be done the same way - clipping them to the first layer and cutting a cavity in the back of the insulated board. Keep your measurements accurate and you can minimise the material cut out. Lightweight things like mirrors and tv's can be mounted direct on the plasterboard without any back reinforcement using heavy duty plasterboard fixtures.

Main advantage is the unbroken base layer of insulation at 80mm thick

ReadySteadyGo

Very interesting idea about the dual layers. I like it. But I dont think my budget will stretch to two layers of plasterboard and two "coats" of labour.

Kitchen units are not decided and nor are rad sizes/types, I would prefer if these decisions did not hold up the decision about height for batons.

I dont really want to loose an Inch of space, to make a hole at the back of the insulation for pipework. And even then, I would be concerned over pipes freezing, air movement leading to condensation and mold.

The kingspan rep, says do not cut the board under any circumstances.

How much space can I allow between the battons and the front of the plasterboard and be confident about mountings? (More space = more insulation)

Someone mentioned you can get a product to re-seal the board where you cut them?

ReadySteadyGo

What do you mean by a service zone. Do you mean some boxing in the corner of a room? Or do you mean baton-ing out the whole wall to make space behind the board? It seems that space behind the board is not recommended, due to increased possibility of moving air, condensation and then mold.

antiskeptic

ReadySteadyGo wrote: »

Very interesting idea about the dual layers. I like it. But I dont think my budget will stretch to two layers of plasterboard and two "coats" of labour.

It wouldn't be two layers of plasterboard. layer 1 (contacting the wall) is insulation only, attached to the wall with a 'mushroom' or two until the final layer is affixed. Layer 2 is insulated plasterboard

Kitchen units are not decided and nor are rad sizes/types, I would prefer if these decisions did not hold up the decision about height for batons.

Wall units usually have a recess at the back - come installation time, there'll a gap between the plasterboard wall and the rear panel of the unit. You could attach rectangular panels of (say) 1/2" ply direct to the plasterboard wall with panel adhesive - the glue spread out over a large area will give massive load bearing capability. Then you fix your units to the ply. Complete freedom on unit placement and no need for battens under the plasterboard.

Rad brackets usually have a large-ish face bearing against the wall. If you tech7-ed the bracket to unpainted plasterboard you'd achieve sufficient load bearing for small rads. For larger rads you could glue a 2x-larger-than-the-mounting-bracket rectangles of 1/4" ply/2mm steel sheet to the plasterboard, then glue the bracket to the ply/steel. Modern adhesives are massively strong. A local sheetmetal workers would guillotine some steel for you for not very much.

I dont really want to loose an Inch of space, to make a hole at the back of the insulation for pipework. And even then, I would be concerned over pipes freezing, air movement leading to condensation and mold.

You wouldn't be loosing space with a dual layer method. You'd have your 100mm insulation and 1 sheet of plasterboard. It's just in areas where pipes are that you've to cut a little insulation back - and then only from layer 2. The pipes wouldn't need insulation (what being buried in it) so you've only got tiny channels to cut out of the insulated plasterboard.

The kingspan rep, says do not cut the board under any circumstances.

How do you fit a socket to the plasterboard then? How do you fix wall units? How do you work the board around obstacles? You have to cut the board at some point. But in this case, you've uninterrupted insulation at the wall and only mildly 'compromised' insulation in layer 2.

How much space can I allow between the battons and the front of the plasterboard and be confident about mountings? (More space = more insulation)

In my original suggestion, any battens will be contacting the back side of the plasterboard - which is ideal. But you don't seem to be able to use battens since you don't know where you want to attach things.

Someone mentioned you can get a product to re-seal the board where you cut them?

No idea why you'd re-seal a board. What seal is being cut?

dunsandin

When we build an extension or dryline a home, we always use 12mm marine ply behind the plasterboard - it allows easy installation of kitchens, rads etc, but it has another huge benefit that outweights the minimal extra cost - it makes the plasterboard super tough and able to withstand knocks and bangs that would break through any single layered plasterboard. We use construction adhesive to glue the plasterboard to the ply as well as the usual screws, and the trades that follow behind the plasterers love it because you can hang anything anywhere with ease. No more Rawlplugs!

slave1

You're probably not going to like this but I carried out a similar job, chased all internal plaster off and fitted 50mm insulation, however I fitted 50mm batons in all the right places to support curtain rails, rad support, unit support etc.
Fitted the batons with 8*100 hammer fixings so they are rock solid, no extra labour cost because I did it myself, not rocket science.
Had to cut the insulation slabs in places however such is the payoff to have solid support in place...I'd be wary of going through 100mm insulation with hammer fixings as your fixings will be 'hanging' a fair way from the wall, just sounds like any units could be weakly support...

ReadySteadyGo

Thanks for all the feedback.

@bbam, do you mind me asking how thick your board was, and what type of wall you were fixing to behind the board? and how heavy the items are that you are fixing to it? And how long ago it was done ;-)

@dunsandin - so you would put 800 of insulation straight on the wall, followed by marine plyboard, followed by plasterboard. How do you fix the marine plyboard to the hollow block wall?

@antiskeptic - what make/brand/type of insulation would you use for the 800mm? Does it come in boards or roll? Will it be difficult to mount the insulated boards "flush" with each other after putting this insulation up directly on the wall. Will that method qualify for the internal, dry lining grant?

antiskeptic

@antiskeptic - what make/brand/type of insulation would you use for the 800mm? Does it come in boards or roll? Will it be difficult to mount the insulated boards "flush" with each other after putting this insulation up directly on the wall. Will that method qualify for the internal, dry lining grant?

Rigid board insulation was the idea - the same size as a sheet of plasterboard. There are various types with different performance levels/prices. Check out the Kingspan site.

There'd be no more problem aligning board edges this way than with an insulated board direct to the wall - the 1st layer is only fixed enough to hold it in place until the 2nd layer is mushroomed to the wall over it.

As for grants? I dunno - but would suspect that 100mm of insulation on a drylined wall is above and beyond the grant requirement so you'd be in special territory with the installer anyway.

ReadySteadyGo

Someone told me you can get a sealant, to spray or pain on the board where you have cut the insulation on the back of it, in order to help improve it's effectiveness. I am not sure if this is a vapour barrier, or a high tech insulation.

If I am going to cut the back of the board, am I better off with a board with the foil at the very back of the board, or the foil towards the front of the board?

I assume the two layer system would cost extra? I might also have to worry about a vapour barrier then?

Audioslaven

Ok i have put in 100mm on the external walls and we put up 4 * 2 to support the kitchen. We cut the boards and filled alot of the space up with expandable foam before slotting the board over the timber battons. We did this just for the kitchen. I used metal (rather than plastic) mushroom fittings for the boards and these are alot better. For other parts I got washers where the 100mm was going into the rafters and where i could apply screws.

In regards to curtains I used 150mm screws and so far they seem to be holding up but time will tell. I did not batton this area out. In regards to rads, I put them on the internal walls where possible rather than the external. I know the whole discussion about placing the rads under the windows but we have full length curtain so moved the rads to internal walls

dunsandin

We always build a timber stud framework inside the blocks to carry the insul/ply/gyp. I also use the thin "alu-bubble" insulation behind the ply, just for belt and braces.

gsxr1

if you are putting 100mm on. Why not just batton the wall with 50mm battons. Insulate between them with 50 mm kingspan and then use a 50 mm insulated foil back slab on top.

simples.

loads of grounds 5cm in and 100mm of inso.

paddy147

gsxr1 wrote: »

if you are putting 100mm on. Why not just batton the wall with 50mm battons. Insulate between them with 50 mm kingspan and then use a 50 mm insulated foil back slab on top.

simples.

loads of grounds 5cm in and 100mm of inso.

Exactly what I did in my own open plan kitchen/dining area.

Works a treat too.:)

gsxr1

here is a home that I have done the same in .



Uploaded with ImageShack.us

2x1 1/s rough battons steel nailed to the wall at 400s

with 50mm inso cut neatly inbetween.

wires have been first fixed neatly in straght lines before inso goes in. Then kingspan is cut from behind to fit over them.

Vapour Barrier .

Then it was slabbed with the composite plaster board.

Is now a very warm draft free home. these wall had a cavity which also really helped with the heat lose.

no complaints after 2 years

Thierry

I need to mount wall kitchen unit (IKEA type) against 100mm insulation layer + plasterboard.
Unfoturnately I do not have the option to add a frame beneath the drywall insulation, as it is already there

So I am thinking of:
1) Fixing a wooden strip on the wall onto which the unit will rest
2) Fixing the unit through the two predrilled holes, (behind the unit, top left and right), using long screws
3) Screwing the unit to the ceiling, reaching the timber joists, by adding two wooden srips (one inside and one outside the unit) for better load support

For 1) and 2) what type of fixing would you recommend? They need to be long enough: presumably at least 150mm
other options??