dry lining help

D

Diyhelp

Guest
Hi,

I recent bought a 1950's semi d, and I'd like to dry line the box room as a starter project.

The walls are cavity, with no plasterboard etc on them (solid to tap)

To save some room, I had planned to just put up treated timber battons and fill them with wool fibre and cover with plaster board.

Do I need any vapour control sheets or anything like that (at the wall level or the plasterboard level)??

thanks in advance
P
 
OP could you externally insulate. its would involve a lot less disruption to your home and reduce the amount of thermal bridging issues.
 
Insulating internally is acceptable in principle, but why are you mixing technologies?

If you mean sheeps woll, wool fibre is a natural material and more used in "breathable" builds.

If OTOH you mean Rockwool or some other mineral wool, fair enoughm but you won't save space with either of them per se.

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Concrete walls will take a lot of abuse, especially there there is a cavity to disperse moisture.

HD insulation - in general - is more thermally efficient than "wool" products in terms of total depth required to achieve a similar thermal performance than any wool prodict and thus you need less overall depth for the same effect.

Even where the dew point occasionally forms within the structure, they are usually durable.

Standard mech-fixed insulated warmboard like Kingspan's Thermawall (no connection) mech-fixed to the walls with no cavity would be a better job.

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But don't just "do a room", because you'll create significant relative cold bridges in the adjoining fabric, particularly in the floor zone.

Important to lift the floorboards than rip out the ceiling to insulate the floor zone.

Specifically DO NOT rip down the ceiling, because what your suggesting will create an interstitial cavity which must be stopped at the underside of the ground floor ceiling to preserve its assumed 30 minute Fire Resistance.


ONQ.

[broken link removed]

All advice on AAM is remote from the situation and cannot be relied upon as a defence or support - in and of itself - should legal action be taken.
Competent legal and building professionals should be asked to advise in Real Life with rights to inspect and issue reports on the matter at hand.
 
Thanks guys,

I should have said I was starting with the box room because I wanted to see what I could take on myself, but will expand the job to the rest of the house before the winter starts proper.

I was at the selfbuild show in citywest a month or so ago and they were recommending a frame with solid insulation board attached to the front of the frame (and nothing in the frame), I thought I might save space if I put glass fiber (rockwool, xtraterm etc) between the studs, along with a vapor control layer, then plasterboard?

Do I need any layers between the wall and the treated timber frame (like a breather membrane one of the companies said it was important, the other said not to bother!)

thanks again
P
 
As suggested by Co2 have a peep at the Breaking the Mould articles.

I have posted a link to the first one
http://www.josephlittlearchitects.com/documents/Breaking_the_Mould_1_Construct_Ireland_Issue_6_Vol_4.pdf

Personally, the timber battens with in-fill loose insulation is tough to get right.

The composite board idea makes for a better job, however there are issues with sockets, radiators, skirting boards etc.

The other consideration is around window reveals, how much room do you have for insulation and plasterboard.

What about the sill board?

Internal dry-lining can be done but you need to think about the whole room and not just stick a few sheets on the external walls and walk away.

On the issue of 'layers' research the recommended processes and you will see where the 'layers' go.

In broad outline, there are 2 types: barrier layers and breathable layers.

If I were you, rather than rush one room now, do the research and get it right, even if you loose a winter. It is much more important to get it right than wrong, in some cases, depending on the degree of 'wrongness' the do nothing option would be better

Keep warm
 
That is a disastrous specification.
You cannot seal the space at top bottom or sides from vapour penetration from spaces that abut it.
It will create a space inside the room behind the insulation board where cold moist air can gather, leading to smells, mould and damp problems.
Treating one isolated room like this is just the wrong way to go - you need to consider the entire house or go the external insulation route.

That having been said if you want to fix warmboard directly to the walls with no cavity, it will have a limited effect but also limited downsides.
Just don't accept details from salesmen at Expos - they aren't architects and have a very basic grasp of building physics, if at all.
They certainly won't be around to remedy any defects or consequence from their advice!


ONQ.

[broken link removed]

All advice on AAM is remote from the situation and cannot be relied upon as a defence or support - in and of itself - should legal action be taken.
Competent legal and building professionals should be asked to advise in Real Life with rights to inspect and issue reports on the matter at hand.
 
hastalavista said:
I have posted a link to the first one
http://www.josephlittlearchitects.c...e_Mould_1_Construct_Ireland_Issue_6_Vol_4.pdf
Click to expand...

Thanks for the link.

I think I've seen this before on Construct Ireland in a less developed form when Joe was starting to feed back his empirical data.
All of what Joe suggests about the drawbacks of the single leaf wall seems to be fair comment.

However most of the inner leafs I have inspected haven't had serious issues with damp build up behind them unless it was water ingress from outside.
The argument that the vapour barrier is ineffective works both ways - vapour moves back in to warm rooms.

As for the graph Joe cites, it looks informative but its not the kind of HVAC graph I need to see.

P. 7 shows discrete measurements of different metrics

P. 10 shows projected moisture build up to 2014

P. 11 the graphs seem to be misplaced on atop the other by accident.

(there seems to be nothing in this on the drying out effect of prolonged cold, dry spells)

The implication of this is that the variable membrane prevents moisture build up whereas as a plastic one doesn't.
But im my experience a normal wall whether cavity or hollow block seems to prevent moisture build up because it can get away on the cold site.
I don't understand Joe's findings, where the permeability of the construction seems to prevent moisture escaping on the winter months unless the external wall has a sealed face.

Oh yes, on Page 7 there is a note under the cross section

"Figure 6: A screen shot of a dynamic display of moisture movement in the wall
(note: this wall has a plastered face between block and insulation
so is not directly comparable to buildups studied below)"

Good job we don't build them like that in Ireland so, Joe.

We studied HVAC and moisture control build up under Gerry O'Brien in Bolton Street back in the eighties.
The graph I need to see is the one where maps temperature against moisture content at the correct relative scales.
Its able to show visually (to use visual creatures, architects and designers) where the overlap and therefore the likely dewpoint occurs.
Dewpoint is where vapour, able to migrate through a substance, becomes moisture, which isn't, and which then causes reductions in insulation value.

The issue tAFAICSis not to decry ventilated interstitial spaces but to use them to take away the moisture preventing it building up in the construction to unsustainable levels.
This is where the current super-insulation and super-sealing strategies seem to start tying themselves in knots for what appears to be very little gain.
Proper ventilation is what houses and constructions supporting human beings require, not sealing.

Breathability is what traditionalists have been arguing for decades, and current knowledge supports it.
You "check" the moisture getting in on the "in" side, and make sure its can get away on the "far" side - thus it cannot build up.

I like where Joe is going with his research, but graphs have to be supported by empirical studies showing real consequences and verifiable cost benefits or they are only paper exercises.
And in all these new technologies, we have to factor in the results of moisture and bacteria moving through new restricted constructions and ventilation systems.

Has anyone done a bacteriological study of MVHR ducting and filters yet?


ONQ.

[broken link removed]

All advice on AAM is remote from the situation and cannot be relied upon as a defence or support - in and of itself - should legal action be taken.
Competent legal and building professionals should be asked to advise in Real Life with rights to inspect and issue reports on the matter at hand.
 


[broken link removed]

http://www.gaiagroup.org/Research/RI/DI/index.html

[broken link removed][broken link removed]

http://www.engineeringtoolbox.com/heat-recovery-efficiency-d_201.html

[broken link removed][broken link removed]

J. Korsgaard, (1991) Mechanical ventilation and house dust mites: a controlled investigation. In: D Van Moerbeke, Editor, Dust mite allergens and asthma., UCB Institute of Allergy, Brussles 1991, pp. 87–89
TAE Platts-Mills, ML Hayden, MD Chapman and SR. Wilkins, (1987) Seasonal variation in dust mite and grass pollen allergens in dust from houses of patients with asthma, J Allergy Clin Immunol 79 1987, pp. 781–791.
A. Leaman, B. Bordass, (1999) Productivity in buildings: the ‘killer’ variables, Building Research & Information 27 (1) 1999 4–20.
M. Paciuk, (1989) The role of personal control of the environment in thermal comfort and satisfaction at the workplace, Ph.D. thesis, University of Wisconsin-Milwaukee, 1989.
G.S. Brager, G. Paliaga, R. de Dear, (2004)Operable windows, personal control and occupant comfort, Ashrae Transactions 110 (2) 2004 17–35.
Bornehag, C.G. et al., 2005. Association between ventilation rates in 390 Swedish homes and allergic symptoms in children. Indoor Air, 15(4), 275-280.
Niven, R.M. et al., (1999). Attempting to control mite allergens with mechanical ventilation and dehumidification in British houses, , Journal of Allergy and Clinical Immunology, 103(5), 756-762
Erhorn, H., 1988. Influence of meteorological conditions on inhabitants' behaviour in dwellings with mechanical ventilation. Energy and Buildings, 11(1-3), 267-275.
 
Thanks for the feedback everyone, it makes interesting reading, I've understood the basic ideas, but financially, I can't externally insulate. I will do the entire house (aside from kitchen area with cabinets and the bathroom because it is fully tilled (but will do when changing those). I had spec'd the windows with drylining in mind so they have larger frames and sill boards.

I will use insulated board from kingspan or xtraterm and mechanically fix this to the wall directly.

Thanks to everyone for the help!
 
Last edited by a moderator:
Diyhelp,

Don't forget to insulate within the floorzone at 1st floor i.e. under the floorboards around the perimeter.
This adds up to a huge area of cold bridge and nothing is preventing moisture migrating to it and condensing on the face of the wall - right next to your joist ends - not a good idea.

If you're thinking of having a go at the attic consider following the line of the roof while leaving 50mm air gap as show in Diagram 11 P. 28 of http://www.environ.ie/en/Publications/DevelopmentandHousing/BuildingStandards/FileDownLoad,1647,en.pdf (TGD F 2009). You may have to increase ridge and eaves venting to suit.
Massively insulating the attic with quilt on the flat can cause a host of problems - search AAM for these.



ONQ.

[broken link removed]

All advice on AAM is remote from the situation and cannot be relied upon as a defence or support - in and of itself - should legal action be taken.
Competent legal and building professionals should be asked to advise in Real Life with rights to inspect and issue reports on the matter at hand.
 
if your changing the windows as well, seriously think about the details around them and how they meet the insulation and air-tightness. also check that theres wall vents in each room and they are clear. otherwise it may be a good idea to put 'permavents' in the windows. lastly, would consider putting one or two data loggers in the wall? the information can be taken of them remotely, one or two might only cost a €100's or so.. and at least you have piece of mind that interstitial condensation was not occurring..
 
Thanks! Actually, as it's the box room for the baby, I was thinking of insulating the entire floor as the room is over the hall and I'd like to cut out the noise (and at the moment the hall is coldest).

I replaced the attic insulation 6 months ago, there's a decent gap at the bases.

Thanks onq and low02!
P
 

Thanks for the links - I have my weekend reading cut out for me!


ONQ.

[broken link removed]

All advice on AAM is remote from the situation and cannot be relied upon as a defence or support - in and of itself - should legal action be taken.
Competent legal and building professionals should be asked to advise in Real Life with rights to inspect and issue reports on the matter at hand.
 
On the subject of the health or otherwise of cavity block dry lining - would it be worthwhile when getting a house externally insulated to remove the internal dry lining and thus the probable damp and mould there?
 
I would prefer you get an expert in, who understands what's causing your damp. but yes where interstitial condensation and surface condensation is an issue EWI will help. but the type of external insulation and render is also a factor that should be considered- you may find that External insulation and a rain-screen cladding offers the best solution where damp and mould are a problem
 
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