flanagaj

If an internal soil pipe comes down the wall and exits the house via a rest bend, is the invert level of said waste pipe governed by the thickness of the floor build up, eg screed, 150mm PIR, 150mm concrete slab, sand blinding, hardcore? Or are those layers irrelevant by the virtue of exiting straight out the house? I am also scratching my head as to how I use a rest bend and Radon barrier to hat on said rest bend when the bend radius is quite large and the Radon membrane is underneath the concrete slab. This will mean that for the barrier hat to be sitting on the vertical pipe, the invert level is forced really deep. I had no intention of having to run a deep invert just because of a Radon membrane.

I do have a piece of ground that I can just dump the slops on. Someone suggested knocking up a plywood 1m2 sized container that they can use.

The brickie and his labourer are now coming along to assist.

What's the pea shingle for?

I'm already feeling very apprehensive. Being a catastrophiser, doesn't help matters.

So, I'm doing it with just the wife and I. We are having a pump though, so hoping that will negate any problems.

I was planning on pouring this all in one shot using a pump. The only part of the step footings I’m scratching my head about, is the distance that I need to allow after the internal cavity wall which is at a lower depth. I have drawn the step footing below, but don’t know where the step goes in relation to the lower 600mm footing.

I just need to make sure that the stress of the first one doesn't kill me first!

Thanks. I am going to knock one of those up tomorrow.

I've got a topcon. It was more for a visual cue when the concrete is being pumped into the trench.

The detail of the step footing. I understand that regs require you to have 2 * the height overlap in the horizontal plane. What I am trying to work out is how you do the step. Would you just step up 450mm in one place and if so, how does the bricklayer tie the block courses into the vertical face of the stepped concrete?

The sectional drawing that the TA did for the split height between the garage and the house is below. So it shows a stepped footing, but the crucial detail is missing. I have learnt a valuable lesson regarding "If you pay peanuts ..." As a result, I am going to play it safe and simply pull the footings through level and just suck up the additional muck away cost, blocks and labour .. I am surprised BCO didn't say "I want to see detail as to the proposed horizontal overlap and where the step up will be placed relative to the internal cavity wall"

I will hammer the rebar into the sides or simply spray lines on the side of the trench.

I went out yesterday evening to sanity check the pin spacing measurements and they were around 50mm greater than my cavity centre calculations. So I then contacted the surveyor who confirmed that his drawings showed a 100mm cavity. Architect then apologised for sending over an old drawing which showed 100mm cavity. This was from when we were going to have a 100mm cavity and use 90mm PIR. so I’ve now taken the afternoon off work to validate and move the pins.

Ok, thanks. I didn't consider using two layers of 75mm instead of a single 150mm layer. I can see that by staggering the joints, you negate any potential cold spots where the insulation butts up together.

Having been unable to find anyone who seems half interested in doing our specified power floated floors, we have decided to go with a conventional ground supported slab build up with the insulation on top of the reinforced concrete slab. I decided to go with 150mm insulation on top of the slab simply because I didn't want to have the really long warm up times I'd get if I had a 150mm slab with a 70mm screed layer on top. Can anyone explain or show a diagram which details how the screed layer, inner block leaf and PIR come together at the door reveals when you have a level threshold. Does the PIR simply protrude into the reveal and mate up against the internal face of the outer brick leaf?

So there has been a cock up. It’s been marked out with a 100mm cavity instead of a 150mm cavity. I’ve just raised this with the surveyor and he tells me that the Dwg file that I provided him showed a 100mm cavity instead of a 150mm cavity. How do people managed to xxxx up the most basic tasks.

Would you still check even though it was set out with a total station? some of the pins are not vertical, so that will skew the diagonal measurement.

I’ll be out with my tape measure later, but I’ll be very disappointed if it’s not 😂

I wasted a weekend and a £100 in timber .. the surveyor chap marked it all out in 2 hours 🙄

I can picture the reaction to that realisation

I bought a Topcon rotary last year. Invaluable piece of kit.

I'm going to bang some vertical rebar into the centre line of the trenches and level the tops with my laser level. I'll spray the tops red to aid visibility. I'm also hiring an inline pump so it can be poured quickly.

I've actually found a surveyor in Southampton who is coming out tomorrow afternoon to mark it out with a total station. Given the cost and associated implications of getting it wrong, it's a no brainer.

This week is looking nice and dry with daytime temperatures in the region of 14c-18c, but with low temperatures overnight. If the concrete is poured in the morning and I cover the trenches with a concrete frost protection blanket, will that suffice and ensure that the concrete doesn't suffer irreparable damage.