Neighbour hasn't rendered block built wall

[jeds]

Building control wont sign off my extension until the concrete block walls are waterproofed.

Never heard so much nonsense. Ask the idiots if they insist on brick walls being rendered?

I could understand if it was built using thermalites...

If anything, that would be around the other way. Thermalites are highly waterproof. Throw a thermalite into a pond - it will float. Come back in 6 months, it will still be floating.

 

[SpecialK]

Never heard so much nonsense. Ask the idiots if they insist on brick walls being rendered?

If anything, that would be around the other way. Thermalites are highly waterproof. Throw a thermalite into a pond - it will float. Come back in 6 months, it will still be floating.

I did try and argue but they are insisting. No idea how to get around it. I will clad/render eventually.
The concrete blocks were bog standard 7N ones from Travis Perkins. No idea on the manufacturer...

Are you saying that a building built in thermalites externally would be waterproof to an equal level as concrete blocks and bricks and will be signed off OK?

This is from building control....

"I hope you are well.
No sorry, weathering (Cladding, render etc) will be required to the block work for us to produce the Final Certificate.
Many Thanks,"

 

[jeds]

What type of wall is it; solid or cavity? Where in the country are you?

 

[SpecialK]

What type of wall is it; solid or cavity? Where in the country are you?

Down south. Its got a 100mm cavity filled with dritherm 32 and thermalites on the inside... It was built 2 years ago and there are no damp issues...

 

[jeds]

Just look at table 4 Approved document C and Diagram 12. If you are in zone 3 or less, face blocks with tooled joints is perfectly acceptable.

 

[SpecialK]

Just look at table 4 Approved document C and Diagram 12. If you are in zone 3 or less, face blocks with tooled joints is perfectly acceptable.

Thanks, That is an interesting document.

Essentially it says blocks should be fine as I am in zone 3 with 100mm of full fill cavity insulation!

Would you say this mortar joint pictured was a "tooled flush joint"?

I need to write a email to them asking for an explanation?

 

[freddiemercurystwin]

No flush is when the mortar is completely in line with the face of the blocks.

 

[jeds]

I'd say a bucket handle joint was good enough. Flush means flush but I reckon they probably meant anything other than a recessed joint.

 

[SpecialK]

I have sent them an email... Hopefully they respond with some reasons why it's not considered water resistant enough to get it's final certificate!

 

[SpecialK]

Building completion cert is on the way!... Thanks jeds.