So better off using PIR then surely?

Posted By: Nick Parsonslambda of over 0.44

Yeah, that'd be poor. ITYM 0.044.

(I know you know and that it's just a typo but others might be confused.)

Posted By: VictorianecoInternal insulation and flat finish, approximately 75m2

What's the u value, prices and is it truly DIYable? If a wall is 8m long hours do you do it in one go? With batons and sections?

Hello Victoria,
Thanks for your enquiry, Bauwer Light is the product of choice in such applications.

The U value would depend on the application thickness and the build of your wall.
Assuming 100mm of Bauwer Light internally (in two application layers finished with 5mm of Bauwer Finish) applied to 225 solid brick wall, would give you an improved U value of 0.54 W/m2K compared to an as-built U value of 2.75W/m2K, 5 times improvement in thermal which is seamless and breathable solution, therefore no bridges of cold, condensation issues delivering an improved comfort with Eco friendly solution. Please see earlier comments on Bauwer "feel warm" performance.

Assuming 50mm of Bauwer Light internally (in one application layer plus 5mm Bauwer Finish) applied to 225 solid brick wall, would give you an improved U value of 0.89 W/m2K compared to an as-built U value of 2.75W/m2K, eg. 3 times improvement in thermal.

Each bag of Bauwer Light (or Standard) delivers one sqm yield at benchmark 25mm thickness, due to Bauwer Light-weight thanks to Perlite filler.

75sqm@100mm would require 4 bags per sqm, or 300 bags + 10 bags of Bauwer Finish.
75sqm@50mm would require 2 bags per sqm, or 150 bags + 10 bags of Bauwer Finish.

100mm option would promotion price about £2,790 including delivery (London area) and including VAT.
50mm option would promotion price about £1,600 including delivery (London area) and including VAT.

It is easier to apply vs traditional plaster due to Bauwer light-weight, please see the earlier feedbacks, you could DIY it, yes. Method statement and the application process:

https://youtu.be/oxogp2uRgaw
http://bauwer.co.uk/templates/Default/images/BauwerLightMethodStatement.pdf

8m wall could be done in one go or in sections as well, with one day gap between the application layers, eg first day 50mm Light, second day 50 mm Light and the third day 5mm Finish. 50mm option could be done in two days.

Regards, Alexander
info@bauwer.co.uk

<blockquote><cite>Posted By: Bauwer</cite><blockquote><cite>Posted By: Nick Parsons</cite>Earlier in this thread there is reference to a lambda value of 0.068W/mK. On my 225 solid brick wall this would, for example, give me a u value of around 1.2W/m2K compared to an as-built u value of 2.1W/m2K.</blockquote>

Hello Nick,
Your statement is only correct for 30mm Bauwer Light application thickness, which is really too thin.

30mm of Bauwer Light applied to 225 solid brick wall, would give you an improved U value of 1.2 W/m2K compared to an as-built U value of 2.75W/m2K, eg. 2.3 times improvement. This calculation assumes 5mm of Bauwer Finish.

As I posted above, higher thickness option should be considered, as 50mm or 100mm (2 layers application).


Regards, Alexander.</blockquote>

Can you give figures for the 50mm and 100mm application to the same reference wall? And also advise on price for each method?

Posted By: VictorianecoSo better off using PIR then surely?

Not really in my view. Perlite is the sustainable material, please see the Perlites sustainability fact sheet:

http://bauwer.co.uk/templates/Default/images/Sustainability_Factsheet_Perlite.pdf

Perlite is used to filter the water and filter wine as well; Bauwer is truly Eco friendly material which improves the home comfort as it highly breathable as well. With seamless application no bridges of cold, so actual thermal performance is equal to the declared.

PIR is petroleum based, poor breathability, potentially introducing humidity issues and inferior thermal performance due to potential bridges of cold....rigorous risk assessment must be implemented in advance, as Nick suggested. Also low declared thermal performance of non breathable boards, might mean an "airplane cabin" scenario with thermal and comfort losses due to condensation, heat loss through excessive ventilation, etc, etc

I would prefer natural, Eco-friendly products to be installed in my home. Please see Bauwer product reviews at:

http://bauwer.co.uk/Products.html


Best regards, Alexander

Posted By: Nick ParsonsAlexander,

I am sorry, I should have said that I was talking about like-for-like thicknesses.I assumed a 'base-case' U value of 2.1W/m2K and 25mm of your insulating plaster with a lambda of 0.068W/mK. Yes, it is really too thin, but if I were looking to go with thick insulation I would (a) lose the nice ceiling mouldings and (b) choose to use wood-fibre or cork with a lambda of 0.042W/mK.

You referred on another thread (http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=14393&page=1#Item_9) to:

''other aspects of thermal performance after installation, which includes thermal bridges for boards, breathability and condensation issues, which impacts real thermal performance after the installation but it is a different topic..''

I agree wholeheartedly that mitigation of thermal bridges is very important indeed, but why do you feel that there is any more of a likely issue with ''thermal bridges for boards'' than with insulated plaster? Poorly-detailed insulation board will leave thermal bridges which could have been mitigated, as will poorly-detailed insulating plaster. On the other hand, good detailing (good practice) with either material will help to keep thermal bridges to a minimum.

Hello Nick,
The logic behind is the number of seams when you would connect the boards together, leveling/preparation of the old walls in order to avoid the gaps, cutting boards to fit the curved, uneven areas, etc, etc

Bauwer Insulated plaster application is seamless, eg no seams, so it is a monolithic structure, no glue, no gaps, no wastage of the board off cuts, etc. If the solid wall is not smooth, Bauwer insulated plaster could be nicely
integrated in such uneven and rough structure without cold bridging and with a little effort as well.


Regards, Alexander

Posted By: Victorianeco

Posted By: Bauwer

Posted By: Nick ParsonsEarlier in this thread there is reference to a lambda value of 0.068W/mK. On my 225 solid brick wall this would, for example, give me a u value of around 1.2W/m2K compared to an as-built u value of 2.1W/m2K.

Hello Nick,
Your statement is only correct for 30mm Bauwer Light application thickness, which is really too thin.

30mm of Bauwer Light applied to 225 solid brick wall, would give you an improved U value of 1.2 W/m2K compared to an as-built U value of 2.75W/m2K, eg. 2.3 times improvement. This calculation assumes 5mm of Bauwer Finish.

As I posted above, higher thickness option should be considered, as 50mm or 100mm (2 layers application).


Regards, Alexander.

Can you give figures for the 50mm and 100mm application to the same reference wall? And also advise on price for each method?

Hello Victoria,
Suggest I replied to your question in my earlier post?

50mm option would improve U value to 0.89 W/m2K compared to an as-built U value of 2.75W/m2K, eg. 3 times improvement in thermal at £1,600 including delivery (London area) and including VAT. It would mean £21 per sqm to you.

100mm option would improve U value to 0.54 W/m2K compared to an as-built U value of 2.75W/m2K, eg. 5 times improvement in thermal at £2,790 including delivery (London area) and including VAT. It would mean £37 per sqm.

Best regards,

Alexander
info@bauwer.co.uk

Posted By: GotanewlifeI have to say I am with Alexander on this. A U value of 0.9 and a loss of space of 50mm with vastly reduced risk of poor detailing compared to boards (incl wood fibre), and no risk of damaging those solid walls with condensation issues and all DIYable is a worthy target - except it is not.....

and the price?

Hello,

We sent few free Bauwer bags samples to the green building forum members and they were impressed with the product application and performance. Bauwer is DIYable yes, that's correct.

Also Bauwer products are produced on the modern, efficient German built manufacturing line, with a bespoke design for the light-fillers products and a state of the art perlite expansion process. Therefore we are able to offer a highly competitive pricing policy which is already led to expansion of the insulated plaster and render market segment in the EU.

Each bag of Bauwer (Light and Standard) delivers benchmark output of one sqm at 25mm thickness, due to only 280kg/m3 density vs 1,500kg/m3 density of traditional plaster or about 400-800kg/m3 of competitor products.

The price per bag is subject to the quantity and could range from £15 per bag to as little as £9 for a large promotion quantities.


Regards, Alexander
info@bauwer.co.uk

More information on Bauwer products attached:

Another two houses in London were upgraded with Bauwer Insulated Render, delivering considerable savings in heating bills and improved living comfort with Eco-friendly solution. Final decoration is being completed with http://www.sandtex.co.uk/masonry

Photo #3

Photo #5

Our latest Bauwer leaflet:

You can add multiple images to a single post by initially adding one image and posting, then using the 'edit' function, add another image, then save changes (repost). You can do that for as many images as you like.

Posted By: SteamyTeaYou can add multiple images to a single post by initially adding one image and posting, then using the 'edit' function, add another image, then save changes (repost). You can do that for as many images as you like.

Sounds like a good idea....thanks! I'll give it a try next time :)