airbrick on an extension

[nalle59]

We are having a small extension built to our kitchen .It is built in concrete with 4 layers of brick at the base and thermal block inside with rockwool insulation between the walls.
Now the question is do we need airbricks? The bricklayer got us to buy three airbricks but he has not used them!! The floor will be concreted with damproof membrane and celotex insulation.
Also can someone tell us how the lintel is fixed to the blockwork over the window opening?
Also where does the wallplate go ?and how is it fixed on?
Thanks .

 

[noseall]

is the existing floor of the house a timber floor construction?

 

[nalle59]

is the existing floor of the house a timber floor construction?

The existing floors are concrete and the new is to be concrete .

 

[Shytalkz]

If he's casting a slab on the ground, there is no void under the floor to ventilate.

Lintel sits on both leaves of the masonry, on either side of the opening.

Wallplate sits on a mortar bed and is strapped down the inside face of the blockwork. It goes under the ceiling/flat roof joists, which are nailed to it.

 

[noseall]

Also can someone tell us how the lintel is fixed to the blockwork over the window opening?
Also where does the wallplate go ?and how is it fixed on?
Thanks .

lintels are usually bedded in mortar. they require no mechanical fixings.

normally, the wall plate is bedded in mortar onto the top of the blockwork or the inner leaf of masonry.

 

[noseall]

bah, beaten by shytalkz again.

 

[Shytalkz]

bah, beaten by shytalkz again.

Dah dah, bow to the mastah....

 

[noseall]

Lintel sits on both leaves of the masonry, on either side of the opening.

not necessarily.

window openings directly below a roof overhang, where there is no masonry showing above (i.e. the soffit is laid on top of the window) there isn't a need for lintelling of the external masonry.

 

[nalle59]

If he's casting a slab on the ground, there is no void under the floor to ventilate.

Lintel sits on both leaves of the masonry, on either side of the opening.

Wallplate sits on a mortar bed and is strapped down the inside face of the blockwork. It goes under the ceiling/flat roof joists, which are nailed to it.

You say the wallplate is strapped down ! with what?

 

[Shytalkz]

not necessarily...window openings directly below a roof overhang, where there is no masonry showing above (i.e. the soffit is laid on top of the window) there isn't a need for lintelling of the external masonry.

Ok, closed eaves detail, no outer section, give you that: 15 all

 

[Shytalkz]

You say the wallplate is strapped down ! with what?

Straps (funnily enough ), usually at 2m centres, L-shaped 900x100, 30mm or thereabouts wide. Short bit goes over the top of the plate and is nailed to it; long bit screwed or masonry nailed to the blockwork.

 

[nalle59]

You say the wallplate is strapped down ! with what?

Straps (funnily enough ), usually at 2m centres, L-shaped 900x100, 30mm or thereabouts wide. Short bit goes over the top of the plate and is nailed to it; long bit screwed or masonry nailed to the blockwork.

You say the Straps are 900x100 , do you mean millimeters? It seem very long at 900mm , can one use shorter ones?
Thanks for all the reply's much appreciated.

 

[Shytalkz]

You say the Straps are 900x100 , do you mean millimeters? It seem very long at 900mm , can one use shorter ones?

well, I wasn't talking inches/feet/metres/miles . If you're in the wilds of Scotland, or in an exposed position on the coast, then I wouldn't advise it, but there are shorter ones available.