Block advice

[DerbyLad]

Hi All,

My architect has specified 100MM PLASMOR FIBOLITE 3.6N BLOCK for the internal block work on my self build.

A few of the builders that have quoted have raised concerns on this type of block saying that they will crack.  I have had a few difficulties getting my SAP requirements and can see this opening up old wounds if I was to change this block.  Would any of you have experience with this block? Is there an alternative with similar u-values that is stronger?

 

Whilst looking at blocks I came across the Marmox Thermoblock for a single course to aid with thermal bridging.

http://www.marmox.co.uk/learning-hub/reducing-thermal-bridging-in-wall-to-floor-junction-designs

Has any one used these blocks?

 

Thank you 

 

[wozza]

We used 3.6n Fibolite without any issues.

 

Ask the builders why they will crack and if they have used them before, are they confusing them with other blocks?

[Oz07]

I don't think there are airated which they are perhaps being confused for

[Mr Punter]

The Fibolite blocks are made with expanded clay beads.  They are not the aircrete crappy ones.

 

The Marmox are good for a single course.  Get your SAP person to let you know if they make any difference to your rating.

[bassanclan]

k = 0.24W/m°C for 3.6 N.
k = 0.28W/m°C for 7.3 N

 

So might be worth running the calcs for the difference

[DerbyLad]

Hi All, thank you for the replies

Sounds like the builders were getting confused with the type of blocks, which is good news in a way!

 

Mr Punter, have you used the Marmox block?

[Mr Punter]

35 minutes ago, DerbyLad said:

Mr Punter, have you used the Marmox block?

 

Not yet but have spec'd it for a forthcoming project where we have to get a minimum 19% C02 improvement over part L 2013.  I was also looking at Foamglas but the Marmox looks cheaper and has higher compressive strength.

[Vijay]

I went with Marmox Thermoblocks which are being delivered tomorrow

[Vee6 dan]

I’ve laid them before. Not too bad to lay, they are only for one course round the bottom tho aren’t they and then normal blocks above 

[Brickie]

A lot of old school Brickies have been schooled to have the mortar far too strong for blockwork which can cause cracking-they then consider the blocks to be too weak without considering the mortar strength. 

[DerbyLad]

Thanks everyone. Looks like I'm ok with the Plasmor block.

Regarding the Marmox block, I have asked my SAP guy for his thoughts on how much difference they would make to wall u-values and my overall SAP.

Thank you Vee6 dan it's good to hear they are quite straight forward to lay and yes, just for one course