Timber frame insulation

eamon11

hello,

Im building a little timber frame house. 2x6 studs, ply on outside.3 inch cavity and 4 inch block wall. Can I insulate between the studs with 150mm earthwool? Or 100mm? The roof has 7 inch rafters. Again, can I use earthwool here between them?
Thanks

MicktheMan

Are these q's not best directed at whichever professional will be signing off on compliance to b regs?

Lumen

That is nowhere near enough insulation.

listermint

MicktheMan wrote: »

Are these q's not best directed at whichever professional will be signing off on compliance to b regs?

That'll be a builder then such is the abysmal compliance system we have on this country..

A country of this size should have council site inspectors. And you have to pay for inspection per each stage.

karlitob

listermint wrote: »

That'll be a builder then such is the abysmal compliance system we have on this country..

A country of this size should have council site inspectors. And you have to pay for inspection per each stage.

Interesting you say that. A very good letter in the Irish times yesterday on that point which made some interesting background to this point that I wasn’t aware of.

Sir, – In response to Daragh Cullinan’s letter (Letters, January 22nd) on Priory Hall and the need for a “properly resourced building inspection organisation”, can I point out that Dublin Corporation’s “bylaws with respect to the construction of buildings”, adopted in 1949, provided just such a structure. Up until its effective abolition by the new “self-certification” system established under the Building Control Act 1990 and subsequent building regulations, everyone seeking to build in Dublin city and county had to apply for bylaw approval prior to construction.

On-site inspections were carried out in all cases, large and small, at key stages of the construction by the surveyors, inspectors and engineers of a large building control section. This was, as a matter of interest, located on the site now occupied by The Irish Times on Tara Street. More detailed inspections were carried out in the case of larger constructions.

As we have learned to our cost, it is simply not possible to retrospectively “certify” that a building has been constructed in accordance with requirements once the bulk of the work has been covered up.

Prior to 1990, every builder in Dublin knew that they had to invite inspections at each key stage of the building process before moving on to the next stage. Failure to do so would – and did – result in a demand that such work be uncovered.

Because there was an obvious need for a national system of building regulation, the Government was faced with the alternatives of extending the robust bylaw systems in place in Dublin and some other cities or coming up with a new light-touch, “self-certification” system. Under pressure from the construction lobby groups, which had long-established links with the main political parties, the government of the day and subsequent governments opted for the light-touch option.

The full impact of this disastrous decision may never fully come to light but we have seen enough evidence already to realise that it needs to be reversed. Apart from issues around fire safety (such as Priory Hall) and pyrites, the lack of adequately enforced standards of thermal insulation has resulted in the need for far more expensive retrofitting of such insulation.

Recent attempts to strengthen the building regulations will not work in the absence of a robust system of staged on-site inspections by independent experts. Unfortunately around 50 per cent of all residential units in the country were constructed after the introduction of the “self certification” system so, to a large extent, the damage has been done. – Yours, etc,

ADRIAN CONWAY,

Chartered Engineer,

Calahonda52

eamon11 wrote: »

hello,

Im building a little timber frame house. 2x6 studs, ply on outside.3 inch cavity and 4 inch block wall. Can I insulate between the studs with 150mm earthwool? Or 100mm? The roof has 7 inch rafters. Again, can I use earthwool here between them?
Thanks

You can do what you like, the question is what building standard, if any are you trying to achieve?
As part of that will be the insulation:
type/thickness/u value/density/ specific heat capacity/ thermal conductivity/ vapour transmission.

The other question is the management of moisture vapour movement.
Put succinctly, if you get it wwrong in the TF construction it will rot from the outside in , end of, period.

listermint

karlitob wrote: »

Interesting you say that. A very good letter in the Irish times yesterday on that point which made some interesting background to this point that I wasn’t aware of.

Sir, – In response to Daragh Cullinan’s letter (Letters, January 22nd) on Priory Hall and the need for a “properly resourced building inspection organisation”, can I point out that Dublin Corporation’s “bylaws with respect to the construction of buildings”, adopted in 1949, provided just such a structure. Up until its effective abolition by the new “self-certification” system established under the Building Control Act 1990 and subsequent building regulations, everyone seeking to build in Dublin city and county had to apply for bylaw approval prior to construction.

On-site inspections were carried out in all cases, large and small, at key stages of the construction by the surveyors, inspectors and engineers of a large building control section. This was, as a matter of interest, located on the site now occupied by The Irish Times on Tara Street. More detailed inspections were carried out in the case of larger constructions.

As we have learned to our cost, it is simply not possible to retrospectively “certify” that a building has been constructed in accordance with requirements once the bulk of the work has been covered up.

Prior to 1990, every builder in Dublin knew that they had to invite inspections at each key stage of the building process before moving on to the next stage. Failure to do so would – and did – result in a demand that such work be uncovered.

Because there was an obvious need for a national system of building regulation, the Government was faced with the alternatives of extending the robust bylaw systems in place in Dublin and some other cities or coming up with a new light-touch, “self-certification” system. Under pressure from the construction lobby groups, which had long-established links with the main political parties, the government of the day and subsequent governments opted for the light-touch option.

The full impact of this disastrous decision may never fully come to light but we have seen enough evidence already to realise that it needs to be reversed. Apart from issues around fire safety (such as Priory Hall) and pyrites, the lack of adequately enforced standards of thermal insulation has resulted in the need for far more expensive retrofitting of such insulation.

Recent attempts to strengthen the building regulations will not work in the absence of a robust system of staged on-site inspections by independent experts. Unfortunately around 50 per cent of all residential units in the country were constructed after the introduction of the “self certification” system so, to a large extent, the damage has been done. – Yours, etc,

ADRIAN CONWAY,

Chartered Engineer,

E.g I watch a decent builder from new Zealand on YouTube called Scott brown. Good show. He plied alot of his trade in Scotland.

Down there you have site inspections per every major milestone and you can proceed with any works until your inspection appointment is completed. New Zealand a population and weather system not far removed from our own. Now obviously they have earthquakes to contend with but their building requirements are all very common sense.

Why do we not have that here. The cost would be on the builder per inspection so the cost to the state should be negligible. It would actively create jobs and perhaps actually allow home builders to comply with proper standards.

Effects

Wouldn't it also make houses that are already expensive, even dearer again?

I'm not saying it shouldn't be done by the way!

listermint

Effects wrote: »

Wouldn't it also make houses that are already expensive, even dearer again?

I'm not saying it shouldn't be done by the way!

Maybe it would but also maybe it wouldn't . Realistically you are trying to cover the wage and costs of such a department. I'd expect a study on that. Costs should maybe be a hundred or so per inspection.

Surely better building for all including refurbs is a good end goal. This scheme should also offer guidance on people doing refurbs concentration on heating and cold..you only have to see the absolute raft of threads in here about this daily to show that people are clueless and getting all sorts of advice from builders.

The government need to do better especially if we want to reach any sort of environmental targets. Can't keep throwing bad heating into poor buildings when replacing oil burners for example.

listermint

Actually I often wonder why the green party isn't pushing for something like this rather than the absolute nonsense they get up to when in government.

It's really a no brainer.

Lumen

I don't see why the cost shouldn't be borne by the State, which makes massive amounts of money from property development. It's in our collective interest to have energy efficient, long lasting buildings but more importantly, the costs scale perfectly with the revenues.

listermint

Lumen wrote: »

I don't see why the cost shouldn't be borne by the State, which makes massive amounts of money from property development. It's in our collective interest to have energy efficient, long lasting buildings but more importantly, the costs scale perfectly with the revenues.

Id like to see state costs going to infrastructure , transport , ports health etc.

That's why I'd be ok with a couple of hundred for a few inspections. Negligible cost for someone spending thousands on a renovation.

Let's say you had ten inspections at between 70 and hundred Euro each could even be scaled per building size. That's not unfair for me anyway. I'd be happy to pay if for reassurance and advice. Works well in NZ.

johney

I thought I was in the DIY section but I guess I was mistaken. I'm in the "extremely cleaver and superior" section. Not 1 person has actually answered the post. The OP is asking for advice on what to do. Ye prance around with lots of "important" comments and like to show ye,re Superior knowledge about building. Lots of "what you shouldn't do" "whats bad" lot of negativity and lots of silly questions. And now a full blown debate and f*** the op and his "silly questions" People here are just too smart to lower themselves to such a level. Can't beat boards for a good kick in the teeth when you try to do something eh? Talk about derailing a thread. Where are the mods now? A lot of BS here lads, try answering constructively for a change, otherwise move on. PM sent.

MicktheMan

johney wrote: »

I thought I was in the DIY section but I guess I was mistaken. I'm in the "extremely cleaver and superior" section. Not 1 person has actually answered the post. The OP is asking for advice on what to do. Ye prance around with lots of "important" comments and like to show ye,re Superior knowledge about building. Lots of "what you shouldn't do" "whats bad" lot of negativity and lots of silly questions. And now a full blown debate and f*** the op and his "silly questions" People here are just too smart to lower themselves to such a level. Can't beat boards for a good kick in the teeth when you try to do something eh? Talk about derailing a thread. Where are the mods now? A lot of BS here lads, try answering constructively for a change, otherwise move on. PM sent.

What are you on about.
Their questions about what can be done were answered to the extent allowed by the information provided by the OP.
Specifically they were advised that it wasn't enough insulation in one reply, that they can build whatever they wanted but perhaps take other aspects into account in another and I advised to seek professional input given the little information proffered in the op.

Yes, there was also a side discussion but that's beside the point.

I notice you have not given any answers to the OP yourself!

johney

MicktheMan wrote: »

Are these q's not best directed at whichever professional will be signing off on compliance to b regs?

ah Mick, you of all people should have remained quiet. Yours was the most stuck up reply there, yet you have the audacity now to come along and try to defend yourself. Careful there Mick, there may be someone out there who does not think the sun shines out your hole, amazing as that may seam to you. Such a "f*** off reply, Person asks for advice. Man replies "dont ask me" Why does man reply at all? Maybe, just maybe, the guy doesn't have a "b reg professional" and is doing it himself. Hence the DIY section... duh. The OP didn't say he was installing 100mm insulation. Did you notice the question marks. He was asking how much insulation he should install. You also conveniently didn't notice the "pm sent" in my post. And you are wrong, again assuming the worst. I did advise the op as much as I could. But not here, for the likes of you to rip asunder. Have a nice evening and stay safe.

eamon11

hear hear...any advance on Johneys advice?

Lumen

johney wrote: »

Maybe, just maybe, the guy doesn't have a "b reg professional" and is doing it himself.

It's all in the TGDs, which anyone building a house should be familiar with. For insulation, part L.

https://www.gov.ie/en/publication/d82ea-technical-guidance-document-l-conservation-of-fuel-and-energy-dwellings/

This has nothing to do with superiority and trying to sound clever, the building regs are complicated, and that makes a definitive answer to the original question impossible, because there isn't enough information to go on.

So the simple answer is "follow the TGDs".

gman2k

eamon11 wrote: »

hello,

Im building a little timber frame house. 2x6 studs, ply on outside.3 inch cavity and 4 inch block wall. Can I insulate between the studs with 150mm earthwool? Or 100mm? The roof has 7 inch rafters. Again, can I use earthwool here between them?
Thanks

Eamonn, the problem with quilt insulation when used vertically is that it tends to sag, leading to cold spots at the top of the wall. It will definitely happen if you use 4" in a 6" stud wall. I would recommend using rigid board insulation.
Another issue with TF construction is the amount of cold bridging caused by the studs. Dry lining internally can reduce this.
To avoid the chance of pi*#ing off the other posters here, do you have a professional onboard to guide you?

Lumen

gman2k wrote: »

Eamonn, the problem with quilt insulation when used vertically is that it tends to sag, leading to cold spots at the top of the wall. It will definitely happen if you use 4" in a 6" stud wall. I would recommend using rigid board insulation.

Mineral wool insulation should be OK as long as it's the higher density friction-fit stuff designed for rafters (e.g. Metac). Quilt insulation is only suitable for horizontal applications.

Alternatively woodfibre (e.g. Gutex Thermoflex), or (as you say) rigid boards.

TimHorton

listermint wrote: »

That'll be a builder then such is the abysmal compliance system we have on this country..

A country of this size should have council site inspectors. And you have to pay for inspection per each stage.

Its incredible , Just crazy that all building work here has zero inspections , I follow Scott Brown Carpentry (New Zealand Carpenter) on Youtube and he is currently adding a modest extension to the back of a house . Every 2nd episode he has council inspections. they check every aspect of the build.

https://www.youtube.com/channel/UC_JILA9Hg517dKdMb3n2OrQ

dathi

TimHorton wrote: »

Its incredible , Just crazy that all building work here has zero inspections , I follow Scott Brown Carpentry (New Zealand Carpenter) on Youtube and he is currently adding a modest extension to the back of a house . Every 2nd episode he has council inspections. they check every aspect of the build.

https://www.youtube.com/channel/UC_JILA9Hg517dKdMb3n2OrQ

https://www.irishtimes.com/news/environment/builders-of-one-off-homes-can-opt-out-of-regulations-from-tuesday-1.2334297

lay the blame there