We recently had a single storey extension to the rear of our house and to save money i've decided to do build the steps down from the bifold doors and re-pave the patio myself. Planning to build two steps down to the patio running the width of the bifold doors, each one being 2 courses high. On the left and right of the patio doors I plan to fill the area with decorative slate/chippings, hence building a 4 brick high wall all the way along (see image). The issue is because of the soil pipe running across the back of the house above ground level on one side I have had to build the wall supporting the top step slightly in front of the pipe (see image). I plan to use 600x600 limestone pavers, however the top paver will come to about 100mm away from the house wall, sitting halfway across the engineering bricks in the picture. There will also be about a 40mm gap between the bricks and the house wall. The pavers should be around 75mm below the damp course and under the door sill, so I dont think there is an issue there, but my question is what should I do with the gap? I have considered filling the gap with concrete upto the level of the bricks and then putting decorating slate in the 100mm space between the paving stone and the house wall. My concern with that though is if water may collect in that space because it's not completely covered by the door sill. Or cutting pavers to fill the gap to pave right up to the house wall. Advice will be much appreciated, also any steer on whether building regs could be affected, we are yet to get final sign off on the extension.
Abrickie is better at this than me..but if he hasn't seen this post... You say DPC is 75mm above and I guess spacing out at other end produces this 100mm gap. I feel just mortaring around / over the engineering bricks will eventually let water in for later freeze and expanding. I would go for filling in the 40mm and laying a cut paver.
Thank you chillmonster, TBH I put my glasses on had a really hard look at the photos and decided that discretion is the better part of valour
Hands up, I did google the preferred gap and it used that phrase. I've just come off Mr. McCormack's revised website to see the latest ( I only get involved in low retrofit steps) and they're now into a waffle board between new brick and existing, I have been leaving a small gap. I'm sure the poster will be using SBR to help hold slabs in place. I love that stuff.
Thanks Chillimonster. Probably not clear from my pics as I haven't finished laying the bricks all the way along yet for the top step. Basically the left side of the bifolds you can see the new extension is sat on a raft foundation. So i'll be laying 2 courses on top of that and then where the raft ends I will be laying 4 courses in order to get a level wall all the way along to support the top paver. I then plan to infill the void area to further support the middle of the slabs and lay on a full bed of mortar. So if I fill the 40mm gap behind the bricks and then cut some pavers to make sure the top step goes right up to the house and under the door sill do you think this will be ok? The pavers should be sitting about 75mm below the damp course, I understand ideally it should be 150mm but from googling around there seems to be a lot of people doing it flush with the damp course even.
Hello Mike , there are a lot of examples of flush with the DPC and some mortared right above the thing. People do this if there is no Buildings Regs approval to be sought. I answered what I would do at the stage of construction in the pictures. I wouldn't comment on what a Buildings Inspector may say, if anything.
Got it cheers Chillimonster, Building inspector should be coming out again soon so maybe best I hold off and put the question to him.