We have removed the pebbledash from our 30s house which had an extension added to it in the 80s made from 'solid' 9' thermalite blocks. This has revealed a few cracks that go straight through the blocks. These are only a couple of mm wide but this is the time to sort it out. The plasterer has suggested that a sheet of expanded metal over the area should sort it out. Is this a sensible option?

1. Thermalite Blocks Price
2. Thermalite Products Inc

Jan 23, 2015 The cracks appeared after about 1 year and run through through the mortar and the blocks down to the damp course red brick line where they stop. I cannot see if they are cracked on the outside as they have built so close to next door. The cracks are a few mm across and appear to be ground floor up to rsj only as far as I can tell. Crack Sealer Plus is a pure injection filler designed to bond those hard to fill narrow cracks in bricks, blocks, render and concrete. Small flexible nozzles enables masonry cracks as.

I guess if it were 2 leaves of brick I would cut out the damaged brickwork and replace but it seems to be more difficult with a solid wall and supporting the existing wall plate.
What about stitching the damaged area? Would this be worth it or just go with the expanded metal.
Thanks in advance.
Matt

Thermalite Blocks Price

Ask a tradesman

Extensions

I've recently built a 2 storey extension and noticed vertical cracks appearing on the internal thermalite/celcon walls. The widest is probably only 1mm wide tapering off to nothing. There's also a number of hairline cracks at various places around the build, all of which are internal. Should I be worried? Do I need to do anything before I board it out? Thanks...Chris

2

2 Answers from MyBuilder Extension Builders

Thermalite Products Inc

Best Answer

24896

Thermalite blocks are prone to shrinkage. so long as the blocks dont appear on the outside walls this is probably the cause. British Gyprum only recommend boarding on thermalite as opposed to wet plaster because of this. Fill the cracks with a weak mortar and board over using dot and dab.

2013-06-01T16:05:02+01:00

Answered 1st Jun 2013

24890

thermalite blocks always crack. I personally wont use them, I use toplite. If you are dot and dab probably be ok

2013-06-01T16:05:02+01:00

Answered 1st Jun 2013

Related Questions

• Victorian solid brick walls-cement and sand or lime render on internal wall

  Our Victorian end terraced house that we moved into in November last year had soaking damp walls which we removed (the plaster...

• Is lime plaster advisable on internal walls separating rooms or only need on external and party

  I’m getting damp blown plastered replaced with lime in 1880s mid terrace but the walls between bedroom and bathroom seam fine....

• Advice needed - Main Walls Issue on Home Buyer Report

  My boyfriend and I are looking to buy our first home and it is an old victorian end-terrace cottage (built 1890) and the house...

• Ytong Internal block wall questions

  Hi We will be building an outbuilding consisting of blocks with cavity walls. the external wall will be concrete blocks whilst...