cavity wall

Hi all Need to gain 20 mm height on soil stack,the point where the soil pipe exits the building,I understand water doesn't run up hill only option I seen to have is relocate exit on gable end and bring around corner, completely out the way.I would also run the two external waste...

Hi guys currently self building single storey extension,all great so far blockwork up cavity 100mm,minor issue I need to gain 100mm in height for ig lintel Concrete block external toplight internal Best options 100mm coursing blocks all the way around ? Or a cheaper way of cutting a few...

Hi my cavity walls fall half a metre below ground,just wondering why a weak semi dry mix is required,I understand for the walls not to cave in,but why a weak mix,couldn't I over order on c25 mix for the floor slab and fill cavity with this,save loads of time.. Thanks

Hi, I would like a view on how best to close the cavities around window and door openings. The wall is 7N blockwork on the internal leaf and rough stone on the outer, which results in a very undulating cavity size. I have 80mm tongue and groove insulation in a 150mm cavity. The stone is at...

I am buying a detached house, circa 1911 to 1926 (not on the 1911 OS map, is on the 1926). Survey identifies empty cavity wall (rather than solid wall) original plaster internally and original lath ceilings. It suggests the exterior render is original, looks ok, however has some loose sounding...

Hi lads Can I use 50mm or 75mm in cavity walling and not use the 100mm, its a small music room extension and trying to cut back in costs? 100mm fully fills the cavity I know but would it be k to not totally fill it. Thanks S

I’m building a rear extension on my end of terrace bungalow, my Architect has specified a 600mm x 1000mm concrete foundation. At the adjoining boundary to next door we have a concrete post fence, the 150mm “toe” of foundation on that side of the 300mm cavity wall will need to go slightly past...

So I’m doing a loft conversion and extension on my 2 bed bungalow, the building regs notes asks for “fire resistant cavity barriers to be installed at tops of wall and gable end walls” anyone know what these look like? And can provide me with a link to the ones I need? It’s a full fill cavity...

I’m building a rear extension on my end of terrace bungalow, my Architect has specified a 600mm x 1000mm concrete foundation. At the adjoining boundary to next door we have a concrete post fence, the 150mm of foundation on that side of the 300mm cavity wall will need to go slightly past the...

Hi all, Just had our upstairs box room re-plastered - old vent taken off, so now an ugly hole into a void... it's a 1940s property - cavity wall - (filled with hay/straw?) and there is an air brick in there. The air brick appears to be blocked from the outside - can't see through it! - perhaps...

Hello, I'm having some work done on my porch. Part of the job is creating a half height cavity wall. The exterior brickwork looks ok, but the interior looks a bit messy. Am I worrying about nothing, or is it important to have a tidy finish inside as well? Please have a look at the pics below...

Hi Do you normally continue the cavity wall insulation up into the gable ends? Is there any point? Cheers, Chris

Hi I am slowly constructing my extension and everything has been going okay until I stumbled upon an article regarding openings near a wall return. It appears you need a 550mm internal return at an external corner although i'm not sure about my instance. It is an internal wall and I have an...

Hi I’ve realised an issue with my extension and hoping for a little input. The building officer has said to cut the brickwork vertically to open the cavity up and I can then tooth the brickwork. The bricks under the lintel (pictured) will then be removed and blockwork rebuilt under it and...

Hi all, Just having a small showeroom refurbished. After stripping down the old wall tiles, my builder said it seems that the window has no lintel on the outer skin! The inner skin seems to be supported on a 'timber' support. The window is upvc and is 50cm wide, and has a height of 90cm. Can...

Good evening everyone. Thanks for a great forum. Our home is a medium to large 1930's/40's semi-detached, made of bottom-half stone and top-half pebble. I'm not sure if this might be important info, but our home elevation is approx 675ft above sea level, although it is on a long flat road...

Hello, I'm having an extension built. The wall is made up of an inner block leaf, an insulation layer (60mm ecotherm), a cavity, and an outer block leaf, with 25mm of external render on top. The cavity was supposed to be 50mm wide but the builder made it narrower (approx 25mm). He insists that...

I have a semi detached 2.5 bedroom house built in the 1890's. The walls are of cavity construction and I believe bricks have been laid with lime mortar. Having removed the wood panelling covering the bottom half of the walls in the smallest first floor bedroom I found the lime plaster underneath...

We are having a ground floor extension built and the insulated walls have been left uncovered resulting the insulation getting soaked through. There has been a delay and they have been left exposed for a few weeks now, and unfortunately there has been a lot of rain. The wall is built with breeze...

Hello, I wasn't sure how to categorise this question so feel free to move it into more suitable sub-forum. I'm looking for some advice. I'd like to route some (7-8) CAT6 Ethernet cables from downstairs living room (router) to the upstairs bedrooms. Most of the cables will be used for...