Polyurethane Form Insulation a good idea?

thebaldwindowfitter

Furts wrote: »

I have not U turned - my position remains as it always was. I would not have the product in my home.

If one puts Technitherm BBA Certificate into Google it comes at the top of the page. Do I really need to provide a link to something so obvious?

My comment on Northern Ireland is to warn you but clearly you feel this warning is irrelevant. To give an anecdotal example had Technitherm been used on my home it would have caused extensive, and expensive, damage. You run this risk but that is your choice.

I repeat my earlier comment - all consumers should read and scrutinise every aspect of the the relevant BBA Certificate before getting insulation installed. We are now on page three of this thread and my intuition is that you have not done this.

Ultimately, you have to decide. If you wish to have the product then you move to the next stage. Buildings Regulations, Approved Contractors, checking them out, inspecting work done, confirming status with CIGA and so on. It has taken 47 posts to get this far, so we could be in for a long ride!

you have infact edited this post because it was here you said you would have it hence my post saying you have done an about turn you may fool some people Furts with your posts

Furts

bluesnake wrote: »

diymonkey, i will come clean. I have in interest in this topic because in the future I (not me really doing the building:) ) would like to get built a Passive House/Net-Zero house, if health allows me. I would not call myself an expert, but I am fairly well read - in theory .

The first thing they do is to put down a moisture barrier and insulate the foundation. They avoid cold bridges. Also the walls are thick with a high R value. They in effect they insulate the outside and put a skin over it. Foam is only used on thermal bridges, the odd inaccessible areas, and thermally sealing joints. They can only spay foam up to a certain thickness. There are problems with the foam if that thickness is too much and is applied in one application.

They all have heat recovery ventilation systems from stale air. Apparently the HRVs recover 90+% of heat which i find hard to believe, and the good one recovers more, and cost less than heating the air.

Loose fill - often treated paper (blown cellulose) is the choice to blow into the walls due to cheap effectiveness. Also loose material, or perlite as recommended by Germans, can be vacuumed out, but this may not be easy, might be time consuming, might be expensive, and you have to store the stuff somewhere, but compared to foam, once is in, I doubt you will ever get it out.

Also in very cold countries, they build off the ground. This stops moisture coming through the ground and into the house. It also stops the house from heating the ground, becoming wet due to thawing, and draining away the heat. Because the floor is so insulated the wind blowing under the house does not significantly cool the house, but does remove the moisture from the land and prevents dampness rising, and rot.

You already sound like you have damp issues which are quite major. These will become worse, and the air will be trapped. I believe you need to sort out the wetness before insulating and have an exit strategy to remove the moisture efficiently, due to laundry, cooking, showering, drying clothes, plants and breathing etc. Also water coming in and/or under your house, and under house ventilation may have to be looked at too.

Just take out a cold beer in summertime and see how quickly beads of condensation appear.

I would guess and I might be very wrong, but if condensation/wetness gets trapped between the outside wall and the insulation, the water will keep cycling through freeze and expand cycles in winter, creating a gap which will either over time push the outside wall out, or compromise the foam until it finds enough heat for it to keep liquid and may even cause water to go into the room. In summer I would expect some water to be absorbed, leaving air pockets which when heated may also expand. to be fair there always will be some water vapour, but if you cant control the external source, you a fighting a loosing battle

When they insulate the outside of a house, I believe they put in a water/moisture barrier on the external walls.

I have built a low energy house to be my home. Not Passiv but it follows similarities with this example. I have Thermobead in the cavities. Unlike Technitherm, this can breath to a far greater extent, and it is also free draining. If things went wrong it could all be vacuumed out of the cavity - just like the above example. Hence three apparent advantages over Technitherm.

Why this product? It was a free installation, but I had first scrutinised and rejected three other cowboy products (including Technitherm) and three cowboy installer companies. However my CWI was installed by cowboys, (cowboys are in the majority in this industry) which shows nobody is immune from being a victim.

thebaldwindowfitter

Furts wrote: »

I have built a low energy house to be my home. Not Passiv but it follows similarities with this example. I have Thermobead in the cavities. Unlike Technitherm, this can breath to a far greater extent, and it is also free draining. If things went wrong it could all be vacuumed out of the cavity - just like the above example. Hence three apparent advantages over Technitherm.

Why this product? It was a free installation, but I had first scrutinised and rejected three other cowboy products (including Technitherm) and three cowboy installer companies. However my CWI was installed by cowboys, (cowboys are in the majority in this industry) which shows nobody is immune from being a victim.

thought i would highlight this because seems strange that you would now call this a cowboy product after al, this time can you tell us your reasons for calling the product that this whole thread is about rather than another sweeping comment . I still ask you to copt and pastethe part of the bba product which says the product cannot be used in ireland

diymonkey

Thanks for your replies guys and a very happy new year!

After careful consideration, I have decided to go ahead with a different company that is also on CHECKATRADE website. They are coming out tomorrow to do a survey and will be doing a boroscope survey which I will also check to make sure the cavity is clear and if so, they will then inject technitherm.

Bluesnake I don't have serious damp issues.. Only a little bit of condensation, mainly on the bedroom windows in the morning which is down to our breathing. To counter this, I will be installing air brick in chimney, more powerful extraction systems in kitchen and bathroom or an air recirculation system in the loft.

Furts I've got to agree with thebaldwindowfitter that you have changed what you originally stated and calling a product like technitherm a cowboy product, yet you think thermabead is superior, goes to show you are just biased. I had exactly these thermabeads installed in my previous property and firstly they caused condensation and secondly they went all over the place. I guarantee you that unlike polyurethane foam, the bonding of these beads breakdowns much quicker and when they do, your going to end up with pockets of empty cavity, which in turn will cause cold spots and damp.

System

Good luck with it.
Get dew point calculations done for each cavity width they measure. To not do this is complete folly no matter what they tell you. If it costs, which it shouldn't, and they try to discourage you from having this information, it's for a reason and you should heed that warning.
It's your home and I hope you don't fall victim to a poor insulation or inappropriate product selection, and you achieve the energy savings promised. Definitely not something I would risk

Furts

diymonkey wrote: »

Thanks for your replies guys and a very happy new year!

After careful consideration, I have decided to go ahead with a different company that is also on CHECKATRADE website. They are coming out tomorrow to do a survey and will be doing a boroscope survey which I will also check to make sure the cavity is clear and if so, they will then inject technitherm.

Bluesnake I don't have serious damp issues.. Only a little bit of condensation, mainly on the bedroom windows in the morning which is down to our breathing. To counter this, I will be installing air brick in chimney, more powerful extraction systems in kitchen and bathroom or an air recirculation system in the loft.

Furts I've got to agree with thebaldwindowfitter that you have changed what you originally stated and calling a product like technitherm a cowboy product, yet you think thermabead is superior, goes to show you are just biased. I had exactly these thermabeads installed in my previous property and firstly they caused condensation and secondly they went all over the place. I guarantee you that unlike polyurethane foam, the bonding of these beads breakdowns much quicker and when they do, your going to end up with pockets of empty cavity, which in turn will cause cold spots and damp.

I explained that I had made a typo and offered apologies for this. I corrected my post to reflect this. If you wish to make an issue of this then so be it.

Regarding Thermabead , it might be that you still do not understand the principles of CWI. I rejected Technitherm because it was a cowboy product for my home, and I stand by that decision. Sales people and surveyors were telling me it was a wonderful product, but it was unsuitable for my home. I knew the BBA terms and it appeared none of them knew these - which is not unusual in the CWI industry.

Moving to your other point, the beads may not stick together but that is not unusual and is a sign of poor installation. Frequently the pva is not being injected in order to speed up work and to save money. Basically a breach of the principles behind the BBA and a failure by the consumer to monitor and inspect. My installers tried this approach and I intervened and stopped the work. There was a blunt ultimatum - do it properly or clear off.

Beads will get through openings in the internal leaf, but these openings should all have been identified on the original survey. Of course they never are and one takes a punt here. However this is again a breach of the principles of the BBA because a competent survey should have been undertaken. If things go badly wrong then it is far easier to sort out beads than Techitherm!

You are wrong to say I am biased - I am simply posting to offer guidance to you. I could not care less what you wish to have installed - that is your decision.

thebaldwindowfitter

Furts wrote: »

I explained that I had made a typo and offered apologies for this. I corrected my post to reflect this. If you wish to make an issue of this then so be it.

Regarding Thermabead , it might be that you still do not understand the principles of CWI. I rejected Technitherm because it was a cowboy product for my home, and I stand by that decision. Sales people and surveyors were telling me it was a wonderful product, but it was unsuitable for my home. I knew the BBA terms and it appeared none of them knew these - which is not unusual in the CWI industry.

Moving to your other point, the beads may not stick together but that is not unusual and is a sign of poor installation. Frequently the pva is not being injected in order to speed up work and to save money. Basically a breach of the principles behind the BBA and a failure by the consumer to monitor and inspect. My installers tried this approach and I intervened and stopped the work. There was a blunt ultimatum - do it properly or clear off.

Beads will get through openings in the internal leaf, but these openings should all have been identified on the original survey. Of course they never are and one takes a punt here. However this is again a breach of the principles of the BBA because a competent survey should have been undertaken. If things go badly wrong then it is far easier to sort out beads than Techitherm!

You are wrong to say I am biased - I am simply posting to offer guidance to you. I could not care less what you wish to have installed - that is your decision.

Why are you calling this product a cowboy product and once again you have FAILED despite being asked numerous times were in the bba spec this product is not suitable for use in ireland very nuch like you have ignored my other request on another thread

27cool

My house has had urethane foam in the cavities ever since I built it in 1977. Never had a damp problem due to the cavity insulation. The back of the house is very exposed to any south westerly gales.
However, I would say that a lot of cavity wall problems are due to the wall ties being covered in mortar, due to slipshod bricklaying. In my case I made sure that the ties were cleared of mortar every night during the build..

Furts

27cool wrote: »

My house has had urethane foam in the cavities ever since I built it in 1977. Never had a damp problem due to the cavity insulation. The back of the house is very exposed to any south westerly gales.
However, I would say that a lot of cavity wall problems are due to the wall ties being covered in mortar, due to slipshod bricklaying. In my case I made sure that the ties were cleared of mortar every night during the build..

I was the owner of a house built around 1972. It had urethane injected at some point during the next ten years. The low level brickwork was spalled and ruined by frost. This had not dried out after heavy rain and been frozen - hence the brick damage.

I post gentle warnings on possible pitfalls. Technitherm will be just the same, and even those who champion it cannot deny these risks.

OP is going ahead so one assumes that all the necessary checks have been made here.

thebaldwindowfitter

Furts wrote: »

I was the owner of a house built around 1972. It had urethane injected at some point during the next ten years. The low level brickwork was spalled and ruined by frost. This had not dried out after heavy rain and been frozen - hence the brick damage.

I post gentle warnings on possible pitfalls. Technitherm will be just the same, and even those who champion it cannot deny these risks.

OP is going ahead so one assumes that all the necessary checks have been made here.

Can i ask if you consider calling companies cowboys a gentle warning . spalled brickwork can happen in all properties as well you would know if you had any building trade experience it doesnt need to be foam injected . Once again you post and have not answered my questions above