Insulated Slabs - Wastes & Showers

[Shaun McD]

1 hour ago, Nickfromwales said:

Yup. From the bottom up. I snip the lighter gauge steel to the same size opening as the shutter, and then back fill retrospectively. It seems like a lot at this stage, but trust me, once the pour is done and you have to get in there to alter, that becomes very small very fast   

 

Fantastic, thank you! Feel much more comfortable with this approach!

Another quick question if you would be so kind, I am hoping to take on the ASHP install, with the external unit outside the utility, where the 300l cylinder will be located. Would you typically take the pipes from the HP through wall (shortest route) or take it under the ring beam and up through the slab?

[Nickfromwales]

4 hours ago, Shaun McD said:

 

Fantastic, thank you! Feel much more comfortable with this approach!

Another quick question if you would be so kind, I am hoping to take on the ASHP install, with the external unit outside the utility, where the 300l cylinder will be located. Would you typically take the pipes from the HP through wall (shortest route) or take it under the ring beam and up through the slab?

Short and sweet  Straight through the wall, sleeved, insulated, and job done. You'll be in the pub by 3  Are you referring to a monoblock? I assume so.

[Shaun McD]

38 minutes ago, Nickfromwales said:

Short and sweet  Straight through the wall, sleeved, insulated, and job done. You'll be in the pub by 3  Are you referring to a monoblock? I assume so.

 

I was referring to monoblock indeed, and I assume it same idea to take in gas pipes if I was going for a split? In general, is one more DIY friendly than the other?

[Nickfromwales]

2 minutes ago, Shaun McD said:

 

I was referring to monoblock indeed, and I assume it same idea to take in gas pipes if I was going for a split? In general, is one more DIY friendly than the other?

Yes, but I'd then tell you how horrible the internal units are to live with, and where best to hide them so they don't piss you off  

Monoblock is 2 pipes, and a couple of wires. I'm not sure I'd tell a complete DIY novice to go for that type of install, but I've eaten so much humble pie I can't fit into my little black dress anymore.

Up to you how confident you are, in a nutshell.

[Shaun McD]

2 minutes ago, Nickfromwales said:

Yes, but I'd then tell you how horrible the internal units are to live with, and where best to hide them so they don't piss you off  

Monoblock is 2 pipes, and a couple of wires. I'm not sure I'd tell a complete DIY novice to go for that type of install, but I've eaten so much humble pie I can't fit into my little black dress anymore.

Up to you how confident you are, in a nutshell.

 

Ha, little black dress was always over rated! I wouldnt consider myself a complete novice so would be interested to know pros and cons of each. I would like to aim for 300l+ of dhw storage, so im guessing that will rule out the split systems with build in cylinders, and not sure if the remaining options are good ones or not. It seems like it makes sense to have the heat transfer happen inside the building envelope, but I would worry that adding on any challenges in dealing with refrigerant may be a pain. Although maybe its all pretty straight forward and could get that filling and pressurising of it done by a pro and still save a lot of money over paying a full system installer?

[JackofAll]

2 hours ago, Nickfromwales said:

Short and sweet  Straight through the wall, sleeved, insulated, and job done. You'll be in the pub by 3  Are you referring to a monoblock? I assume so.

Probably a stupid question. Would you need to put airtightness tape around the entrance/exit holes? Thought drilling holes in walls is a big no no in low energy houses.

[SuperJohnG]

On 14/03/2023 at 23:25, Shaun McD said:

 

Thanks @SuperJohnG I am guessing you could cut them down flush with the slab is needed? Dependent on the correct reducer fitting

I couldn't as you need to add a solvent weld fitting to turn into a ring seal run. You could get lower if you bring a ring seal pipe through levelling the slab or wrap something around the 110mm pipe so you can fit a coupling around once it's cured. I did have a ground floor shower and I didn't want a plinth so I put an EPS  block around the 110mm pipe creating a void which I then dug out. 

[Nickfromwales]

10 hours ago, JackofAll said:

Probably a stupid question. Would you need to put airtightness tape around the entrance/exit holes? Thought drilling holes in walls is a big no no in low energy houses.

That depends on whether it's an airtight dwelling or not. AT detailing is done on the interior, and weatherproofing on the outside. Illbruck 330 foam is your friend for AT work, plus whichever brand of AT tape you prefer.

Drilling through AT houses is unavoidable, unless you're a micro-managing super-human, so panic yea not  I drill through each clients dwellings probably between 5 and 20 times, sometimes more, but AT test results always come in ( on MBC's stuff anyways ) at sub 0.4 ACH, because I make VERY good, each hole I make.

 

[JackofAll]

2 hours ago, Nickfromwales said:

That depends on whether it's an airtight dwelling or not. AT detailing is done on the interior, and weatherproofing on the outside. Illbruck 330 foam is your friend for AT work, plus whichever brand of AT tape you prefer.

Drilling through AT houses is unavoidable, unless you're a micro-managing super-human, so panic yea not  I drill through each clients dwellings probably between 5 and 20 times, sometimes more, but AT test results always come in ( on MBC's stuff anyways ) at sub 0.4 ACH, because I make VERY good, each hole I make.

 

Be alot easier than routing under the slab,  thanks for that @Nickfromwales 

[Shaun McD]

12 hours ago, SuperJohnG said:

I couldn't as you need to add a solvent weld fitting to turn into a ring seal run. You could get lower if you bring a ring seal pipe through levelling the slab or wrap something around the 110mm pipe so you can fit a coupling around once it's cured. I did have a ground floor shower and I didn't want a plinth so I put an EPS  block around the 110mm pipe creating a void which I then dug out. 

 

I am hoping this approach of wrapping most of the 110mm risers in a 200x200 shutter or foam will give space to cut down and reduce below FFL and just have the right size waste rising from FFL in the correct position. Mine is a single story house so im guessing only the toilet wastes can be confidently put in without leaving for some wiggle room.

 

4 hours ago, Nickfromwales said:

That depends on whether it's an airtight dwelling or not. AT detailing is done on the interior, and weatherproofing on the outside. Illbruck 330 foam is your friend for AT work, plus whichever brand of AT tape you prefer.

Drilling through AT houses is unavoidable, unless you're a micro-managing super-human, so panic yea not  I drill through each clients dwellings probably between 5 and 20 times, sometimes more, but AT test results always come in ( on MBC's stuff anyways ) at sub 0.4 ACH, because I make VERY good, each hole I make.

 

 

In real world terms, how much more complicated is this when it's an external block skin? Taking pipes, wires etc out before insulation and with access to both internal and external faces of the frame is ideal, but if there is blockwork built, what is the best way to go about taking out something bigger than a small conduit?