Replace external garage window with door

21 Oct 2010
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United Kingdom
Hi - I have an external garage constructed out of single skin concrete blocks and outside rendering. There is a window on a side wall that I want to replace with a brand new upvc door. The window has a concrete lintel on top. Since the door I intend to fit is narrower and will fit within the space of the window, am I right in thinking that cutting the wall down to fit the door and bricking up the left over window whole is all non-structural work and therefore relatively safe to do - since I am not touching the lintel OR the wall on which the lintel is supported?

Also, I am not sure what the "lip" is at the bottom of the wall of the garage, which I will have to cut if fitting the door. Anything structural that I need to be aware of?

Finally, is it enough cutting the blockwork and fitting the doorframe that comes with the door or must I fit wooden pillars to each side of the door opening? (Door will be like this one: Thank you!
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That lip is only in the render, think its called a bell moulding, its so water drips of the render and does not run down the brickwork. You do not need a wooden frame, use frame fixers (its in the name!) straight through the plastic frame into the edge of the blockwork.
Your biggest problem will be fixing your new skinny wall to the edge of the existing blockwork. I think you will need a ralwplugged in tie on every third course of bricks, at least.
I would mark out the nominal dimension of the door frame on the wall, and cut through the render about 10mm outside it, then cut through the blockwork to the line and take it and the window down. The bell moulding will have some sort of edging strip in it so cut through this with your disc cutter. Then fix the door with frame fixers and make good the render on the cut edges, just overlapping the door frame for a good weather seal, then 5 coats of paint.
Thanks Frank - re the lip, is it OK to cut through all of it to make the door opening, i.e. all the way to the ground?

The little wall hole I need to brick up is 35cm wide by 80cm high - so 4 cut blocks. I am not sure what rawlplugged tie you are saying I should use - please could you explain or provide a link? Will mortar not be enough to fix the new blocks to the existing blockwork edge?
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You have a sand & cement plinth at the base of your wall, and its fine to cut thro it. Its also fine to do what you propose - set your door back from the face of the wall: if possible 75mm is recommended.

Mfr's Inst's should tell you the correct rough opening needed.

Plinths should not be in ground contact or they will wick up moisture. Its advisable to cut the plinth back up by about 50mm - on all walls.

FWIW: The term is not bell "moulding" - the correct term is bell cast - which you do not have.
Frank - thanks for the link, I know which ones you mean. I'll fit them all around the existing masonry for good measure.

Ree - thanks for your response. I took a picture of the opposite wall, where the plinth hasn't been rendered over and you can see it is just a course (or two) of brickwork. Please see below. Is it still OK to cut through it all the way down to my patio slabs? In the second picture I show how both walls of the garage have different height plinths, and different ground levels adjoining it. Unfortunately the ground next to the wall onto which I will fix the new door is higher and I will need to fit a shorter-than-normal door...


You can safely cut thro the "plinth" brickwork

You seem to have areas on all(?) sides of the garage that will allow water access, maybe the car port will cover one side - but not much to suggest or to be done about any water ingress on the other side.

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