PeterStarck

It seems to me there could be more potential problems with a metal web joist ground floor than concrete. So I would use concrete.

That type are around 2.5mm thick steel because they are folded so don't need to be thick like a flat bar. They should be supported in the centre until the blockwork has set, especially if a long length, as @Russell griffiths has indicated. If you saw blocks being laid with the lintel unsupported have a word with the builder.

Do you think it's a flat steel bar like I was referring to or something like this. Did you see it being fitted. Catnic Lintel ANG 2400mm

What roughly is the thickness of the steel. The only flat steel lintel in my old bungalow was around 1/4" thick and the opening only about 2' wide.

I have that fitting on top of my waste stand pipe and it doesn't cause any problems. I can only think that the resistance of the S bend allows the fitting to fill up and vent water through the air vent.

@Home Farm Do you use the chimney now or are you likely to want to in the future. A friend of ours removed one of his completely.

I can't see the problem. It's a total of 2150-920=1230mm difference. 600mm each side or the whole 1230mm on one side. It can still be blocked up without ties or put some noggins in the frame and tie onto those if necessary.

Ask your builder if he can do what @PeterW has suggested. Edit : Sorry cross posted.

If the difference is only 25mm can't the window be made 25mm wider or am I not understanding this very well.

I think that is what I was trying to say. The opening in the block outer skin can be made narrower with blocks and an equivalent opening in the timber frame made by adding timberwork. Then insulation added to the area around the opening. Whereabouts in the depth of the wall are your windows being fitted?

On my system there are four ventilation levels. #1 for when the house is unoccupied #2 normal ventilation #3 increased ventilation #4 boost So I set it up for level 2. The supply and extract motors can be set up independently for all levels. Level 4 is 100%. I set level 3 to be halfway between 2 and 4 and level 1 to be halfway between zero and level 2. I put an entry in my blog about commissioning the MVHR system.

This is how I set mine up for PH levels. MVHR Calculation.pdf

Hi Al. It seems everyone is welcome here as long as they don't use the forum to advertise their business.

@SamuelBombero Welcome to the forum, sorry your hopes have been dashed. I don't know why but maybe someone will explain the reason.

Shouldn't the lead flashing go over the fascia rather than under it?