Brick up a bathroom window

[cubix]

I have a 1950s house with exterior walls made of aerated concrete (Siporex) where we have relocated the bathroom. Where the old bathroom window is located, I plan to brick up the opening after removing the window. The hole is approximately 65x70x35 (WxHxD), and the question now is whether I should use lecabloc, aerated concrete blocks, or what, and which mortar I should use that works with the old Siporex wall and the new material. Should I use reinforcement?

 

[MaxPax]

B or C blocks should work well for building with. The wall has held together for 63 years without reinforcement in that spot, so you don't need to reinforce it. In terms of masonry, it doesn't really matter which blocks you use, but lightweight concrete has better insulation value, which is why I would choose them.

 

[cubix]

Okay, no that's true regarding the reinforcement. It will be lightweight concrete blocks then, with B- or C-mortar. Thanks for the answer.

 

[cubix]

Seems difficult to find aerated concrete blocks with the width I need (30-35 cm), wouldn't leca blocks work just as well?

 

[MaxPax]

It probably works just as well, but as mentioned, you won't get as good insulation value on that particular wall piece. It might be negligible in this case, but someone else can chime in on that, I don't know.

according to this thread: http://www.byggahus.se/forum/stenhus/26570-leca-kontra-lattbetong.html:

Lambda value leca = 0.20 W/mK
Lambda value lättbetong = 0.09 W/mK

you choose...

 

[cubix]

Hmm, it's worth thinking about.....