Ceramic building blocks

[Torchia]

I am thinking of a self build with ceramic building blocks (fired clay blocks). Nearly half of German houses are build with them, but have not seen any build in UK.

 

Can I use this building technique in UK?

What will be the challenges with building regulations/inspector? 

What documentation/specifications will be required to build with them?

 

 

[Russell griffiths]

There is a new house down the road from me built in them, I called in to have a look and was very surprised at the amount of insulation they had to add to the blocks, it was in effect that the blocks added very little to the insulation value.

 

have you looked into the u value you can get with them. 

[Torchia]

5 minutes ago, Russell griffiths said:

There is a new house down the road from me built in them, I called in to have a look and was very surprised at the amount of insulation they had to add to the blocks, it was in effect that the blocks added very little to the insulation value.

 

have you looked into the u value you can get with them.

That is the point, you can build structure quick and cheap. Then add 30-40cm of insulation, render it and you have nearly a passive house.

 

Can you share the location please? I would love to speak with a builder.

[Tennentslager]

Interesting...

double wall them and have UFH and it’ll be like a a Roman villa but probably very very expensive 

Ask @Brickie and @Brickforce69

Edited March 27, 2020 by Tennentslager

[Torchia]

4 minutes ago, Tennentslager said:

Interesting...

double wall them and have UFH and it’ll be like a a Roman villa but probably very very expensive 

Ask @Brickie and @Brickforce69

Thanks for recommendations.

 

The single wall 250mm thickness a very cost effective on labour.

 

[Archer]

You shouldn't have any issues with Building Control, clay blocks may not be common but they are recognised and large manufacturers (Wienerberger etc) have got fully accredited products and loads of technical information. The BRE have a house built from solid wall clay block at their innovation park in Watford. You can visit it if your interested (obviously not right now). 

 

Exeter City Council built a 26 home passivhaus development using this method - Chester Long Court. Link below. 

 

https://www.passivhaustrust.org.uk/news/detail/?nId=791

 

[Archer]

Google search NBT Thermoplan and they have a system with BBA certs

[jfb]

I believe the first course has to be layed very precisely to make the rest go smoothly. Something to think about when hiring workers and assessing their work.

[Archer]

Probably also worth saying that you can also build in a similar way with thin joint mortar and solid wall with EWI using 215mm depth aerated concrete blocks. It's probably significantly cheaper and should be easier to find contractors. If you go for conventional mortar then even more so. 

 

The advantage of thin joint mortar is supposedly increased airtightness and requires less skill in the install so DIYable. But you have to get the first course precise as jfb says. The clay blocks use a vertical groove instead of mortar on the vertical block end. Also you can supposedly get a wall U-Value of 0.2 using a single 425mm block with no insulation. This falls short of the Part L regs I think so you'd need EWI or insulated plasterboard. 

Edited March 28, 2020 by Archer
Correction

[ToughButterCup]

12 hours ago, Torchia said:

I am thinking of a self build with ceramic ....

What will be the challenges ....

 

Lack of local experience.

For the word  ... ceramic... substitute any build material or method that's even slightly outside the range of experience of local tradespeople and, based on my personal experience,  you will hear a continuous sucking of teeth akin to a bad dose of tinnitus. 

 

As you might expect I am very keen indeed to see your project succeed.  I nearly chose your preferred build method too. 

Good luck. Ian 

 

[scottishjohn]

25 minutes ago, Archer said:

The advantage of thin joint mortar is supposedly increased airtightness

its not just that 

think they reckon that 20% of a block wall is mortar --so little insulatin value --thin joint nearly all wall is insulated block 

[PeterW]

Porotherm is probably the best known of the non standard block construction methods - think someone on here has built with them. 

[Russell griffiths]

I think one type don’t even use mortar, they use an expandable foam from a gun, very easy to use looking at the house near me. 

It’s  near Cirencester @Torchia

[scottishjohn]

2 minutes ago, Russell griffiths said:

I think one type don’t even use mortar, they use an expandable foam from a gun, very easy to use looking at the house near me. 

It’s  near Cirencester @Torchia

another system to investigate

[AliG]

That’s me.

 

The Porotherm was recommended by the SE. Really though having looked at the specs and the build I don’t see any benefit versus any other blocks using a thin joint system.

 

The blocks were laid by normal brickies. They flew up on a straight wall with no openings but they struggled when it came to cutting openings. In the end the blockwork took massively longer than expected to go up.

 

The blockwork has a parge coat for air tightness but there are still all the issues you get around windows and joints that require good detailing by the builders no matter how you build.

 

The main issue they created build wise was attaching the windows to them. They crumble when you put fixings in them. For some things you can drill a hole and fill it with adhesive but windows have so many fixings.

 

In the end we had to put ply frames around the window openings to attach the windows.

 

We have a cavity wall 100mm porotherm 50mm gap 100mm pir 100mm block 37.5mm insulated  plasterboard on dot and dab. The quoted u value is low.

 

I wanted to build in ICF and think it would be much better, I just couldn’t find a builder who had used it before.

I would actually stick with timber frame unless you need to use blockwork. We have concrete upper floors so it was necessary.

There might be a big efficiency benefit on a single skin wall but that would be a quite unusual build.

 

 

Edited March 28, 2020 by AliG

[Mike]

18 hours ago, Torchia said:

I am thinking of a self build with ceramic building blocks (fired clay blocks).

What advantages do you hope to achieve?

[Torchia]

26 minutes ago, Mike said:

What advantages do you hope to achieve?

Single skin with blocks - huge saving on bricklaying and time, structure can hold intermediate concrete floor, with 300mm EPS skin you can achieve passive house wall U values.

[Mr Punter]

2 minutes ago, Torchia said:

Single skin with blocks - huge saving on bricklaying and time, structure can hold intermediate concrete floor, with 300mm EPS skin you can achieve passive house wall U values.

 

You can also do this with normal or thermal blockwork.

[PeterW]

As per @Mr Punter you could do this with 140mm medium density blocks and achieve the same for less cost and probably quicker too. The use of non-standard blocks may cause you problems with supply and also potentially mortgage companies who don’t like things that don’t fit their standard boxes. 

[scottishjohn]

so the only real adavantage is speed of build -If you first row right --eg saving on labour 

is that a good sumation of it

 so why has it been a preferred method in europe for so many years in some areas?

Edited March 28, 2020 by scottishjohn

[scottishjohn]

pprobabl y southern europe where cooing insummer is more of an issue ,as they don,t use lots of insulation on those builds

[Mr Punter]

Just now, scottishjohn said:

so the only real adavantage is speed of build -If you first row right --eg saving on labour 

is that a good sumation of it

 

From @AliG's experience it seems fine for large single skin walls without openings and nothing needing to be fixed to them, otherwise, not worth the bother.

[PeterW]

3 minutes ago, scottishjohn said:

 

 so why has it been a preferred method in europe for so many years in some areas?

Because a lot of those countries don’t have the raw materials for concrete blocks - or fly ash blocks - and have a history of brick making. These are essentially hollow or extruded bricks so are fired in the same way as a brick. 

[Brickie]

I’ve not used Porotherm but know of people who have-one fella raves about the speed & stability achievable. The issue with openings & fixing to reveals must be common so surely the manufacturer has a system on their website?

Edited March 29, 2020 by Brickie

[Mike]

I've not used them but  did consider them for a project a few years ago. I'd suggest that their main advantage over aerated concrete blocks would be their resistance to cracking (so no need for bed reinforcement and fewer movement joints required). If you could buy the perlite-filled versions in the UK - when I looked you couldn't - then their improved thermal performance would significantly boost their attractiveness if you need to minimise wall thickness. Maybe it would be economic to import them in those circumstances?

 

Compared to concrete blocks their main advantage would be their light weight for similar or better load bearing capacity.

 

Fixings are not supposed to be a problem provided you don't attack them with a hammer drill, but @AliG obviously found otherwise. Regular wall plugs are supposedly OK for light to medium loads, with chemical anchors for heavy loads.