Please offer observations to this total amateur re conservatory groundworks

Inforapennyinforapound

I am not a builder,never have been,never will be BUT I do have common sense(possibly).

i am having a small conservatory built and the Company have employed their builder to build dwarf walls etc in readiness. I have some observations and questions and would like some guidance please.

The builder has completed. Nice guy and good work as far as I could see and I thanked him. 

During the work I reminded him it needed an airbrick ( wooden floor). I remembered the Company mentioning this. I repeated this to the builder but he failed so at completion I mentioned again and he took out a brick and put in the airbrick .

This put me on guard and then I remembered the cavity wall insulation being left outside in the rain( woolly/ fibreglass type). When I got home and checked he had inserted the wet insulation( remember I know nothing about building). I mentioned it but I was told not to worry as it will dry…am I stupid? Maybe. But isn’t a cavity supposed to be dry?

He put polythene on the floor and left. Of course the whole work is open to the elements and the heavy rain has just made the insulation and brickwork wet through! 

I decided to buy a huge polythene sheet to cover the whole area and then on a sunny day took as much insulation out as possible( couldn’t take out insulation under the wall ties). I tried to dry it but too wet.

Anyway, those are my observations and now questions:
I have decided to remove all insulation that can be reached. Have I done the right thing?. So now most of the cavity is open should I buy more insulation or in fact leave it as I understand a cavity wall in itself insulates. Perhaps insulated plasterboard instead?? The conservatory isn’t yet built ,obviously,so this would be done at final stage.

Finally the builder took away a small section of garden to leave a gap between the conservatory and garden(the garden rises from rear of house.) He built a small (retaining) wall approx 20 feet long and less than 2 feet high. Nice looking wall actually but I noticed no weep holes at all. Maybe doesn’t need them. Maybe I am overthinking everything. Getting stressed over it now and I know nothing about building. I did once cement a few bricks to make repairs😀

I would really appreciate any comments from the wise ones on here who have managed to read this far. Thanks in anticipation.

grumbler

Bricks are porous and the insulation would dry eventually. Don't leave the cavity empty.

For a cavity wall, it has to be an airbrick and a plastic channel going through both the inner and outer skins. However, a suspended timber floor makes a conservatory even colder and difficult to heat than it naturally is. You should have gone for and insulated suspended beam and block floor instead, but now at least make sure that you have good and reliable insulation between the joists.

Drain holes in the retaining wall wood be nice, but IMO aren't necessary if water can escape on the sides of the wall. I hope that your 2 ft retaining wall is at least full-brick (20+ cm), not half-brick.

stuart45

Have you got a few photos?

Inforapennyinforapound

Will try to add photos. Left polythene partially in place..cumbersome

Inforapennyinforapound

Only a small lean-to

grumbler

grumbler said:

I hope that your 2 ft retaining wall is at least full-brick (20+ cm), not half-brick.

Half-brick - as I suspected. Hopefully, the curvature will make it stronger and stable enough.

Inforapennyinforapound

grumbler said:

grumbler said:

I hope that your 2 ft retaining wall is at least full-brick (20+ cm), not half-brick.

Half-brick - as I suspected. Hopefully, the curvature will make it stronger and stable enough

Don’t understand half brick term. Do you mean the wall should be 2 bricks in depth i.e like a cavity wall build without the cavity?

Inforapennyinforapound

Also hope the air brick goes through cavity via some sort of channel… I have doubts especially as it was done after completion. How do I check ?

DanDare999

Inforapennyinforapound said:

Also hope the air brick goes through cavity via some sort of channel… I have doubts especially as it was done after completion. How do I check ?

Is there only one? I would have expected them to be on the other wall and inline with ones already on the house. 

stuart45

You should have a cross flow for underfloor ventilation. I doubt if there's a liner through the cavity if he put the air brick in later. 
The question of the insulation. I always try and keep the cavity batts dry, but on site they often do get soaked and aren't replaced. Manufacturers will say replace.
He has used the wrong size wall ties, that's why they are angled. They should be every block at the reveals.
The setting out has left the wall with large cross joints.

grumbler

Inforapennyinforapound said:

grumbler said:

grumbler said:

I hope that your 2 ft retaining wall is at least full-brick (20+ cm), not half-brick.

Half-brick - as I suspected. Hopefully, the curvature will make it stronger and stable enough

Don’t understand half brick term. Do you mean the wall should be 2 bricks in depth i.e like a cavity wall build without the cavity?