Help me with a basement light (/window)

[2Btoo]

Guys,

We have a basement in our house which is currently scruffy and we're trying to do something with it. The current question is what to do with the window.

Here are some photos, showing how it currently is on our drive.







Here's a view from the inside:



The current plan is to remove the grate and install both a horizonal window to cover the ground and a wide but not very high vertical window to fill in the space in the wall. The glass for both of these will need to be strong - particularly for the horizonal one as it is possible that it will be walked (or even driven) on. We'll then remove the sash window inside, clear out the alcove, insulate and plasterboard the space that is created.

Is there anything in particular I need to know about this? Specfically:

What spec of glass should I buy?

I intend to cut a rebate in the existing concrete slab and let the glass into this, and cut a similar rebate into the render on the wall and let the vertical window into this. Would this work?

There will be an L-shaped join between the windows but I don't think this needs to be structural. Can I simply but the windows up against each other and seal the gap with external grade silicone (or similar)?

The current arrangement allows a lot of ventilation into the basement, which we will lose if we seal it up with a window. I presume I will have to put in an air brick somewhere. How should I calculate the size of this air prick? (I presume there are specifications or regulations somewhere).

Thanks for your help!

[ferret50]

I would investigate lantern windows, the sort of thing that you see used to light ground floor extensions that look a bit like a pyramid....but have it made with an open back that can be mounted to both the wall and the driveway surface. I'd protect it from possible traffic incidents with a fence at bumper hieght!

Ventilation?
Air Source Heat Pump, often refered to as aircon, pumps fresh air in and extracts damp air out.

Good luck with the project and please keep us updated.

[2Btoo]

Thanks Ferret. A lantern window isn't something I'd thought of but it's an interesting idea. I'm not sure it would work because - as you said - it would be very vulnerable to people parking on the drive and knocking it, and putting a fence in would be both ugly and faffy. I'll give it some thought though as it's a very good idea.

Tell me more about ASHP's; I understood that they either cooled or heated existing air, with only coolant being exchanged between the outside world and the inside room (as part of the coolant circuit). 'Pumps fresh air in and extracts damp air out' sounds like a dehumidifier to me.