Nickfromwales

Thanks for the pics. So you have a single CH flow temp, and no differentiation between UFH requirements and those of the rads. Not a great setup afaic, so I’m not surprised it’s not ‘doing exactly as it says on the tin’.

That’s a glass half full moment, c’mon! Kudos to them taking ownership, and in the grand scheme this is a drop in the ocean, surely?

Most will go ‘bonkers’ to protect the system as their arses are in the sling if the system fails and the dilution is deemed to be the cause of the issue; if it’s investigated and found to have been too close to the wind / insufficient. Not so much of an issue if CE are supplying and installing and then servicing and maintaining it, but a different kettle in other circumstances I’d guess.

Ah. 6T to grade, but 3 already down. Yatzee!

New builds and conversions / change of use etc only atm afaik.

Ok then. Let’s stay up and fight this out! If there’s a duct, that means atmospheric conditions can / will exist there, plus ground moisture (damp); so you’ll have it from ‘both ends’ if you create a barrier with the foil. The condensation on the pipe comes from you / the house air, sweat from the ground would collect on the underside of the foil from the subterranean aspect. Just give me your bloody postcode and I’ll bring some pipe insulation and fit it for you, then it’s off to the pub for beer. You’re paying 🍻

Well if we can’t blame you, then you’ve just removed this evenings fun. Its a lot of work to hose the fines out of 3T!!

Then it’s you vs the rest of the world with that thinking. Oak = hardwood to every person I’ve ever bought it from, or fitted it for.

Airtightness and a quality MVHR system will be your biggest return on investment. Insulation plays second fiddle to these, as cold air infiltration (draughts) will promote ventilation heat loss vs fabric heat loss. Fabric one is relatively simple to top up if you get airtight and keep the place from becoming excessively cold in the first place.

Humid air is in the house. That hits the cold pipe and condenses. It’s coming from the depths of your house lol 😜. People breathing, washing machine, tumble drier, dishwasher etc. Please don’t go digging the floor up to look for the source, you’re the source.

I don’t think it is. The pipe just needs simple pipe insulation. Wrap the insulation with duct tape to stop the seam opening and that’s it. Simple!

There’s going to be movement, so I’d rather manage it and ensure it doesn’t then migrate further out, at a weak point in that complex bead. If you do as he says, and stop the render at the frame, then all you need is a decent “mastic man” to put the flexible seal at that point to allow the movement to happen behind it. Somethings gotta give, and you’re trying to remove the ‘give’.

Because the too will be warm, at room temp, and will pull the moisture up to it. It’s an odd thing (not really a phenomenon) but I saw this with a thermal (foil) underlay for laminate flooring, and it was sopping wet under it. The PIR idea is a bit OTT, and doesn’t wrap around and remove the air gap, unless you use foam to seal as well…. but messy and complicated.

They’re all single cell / partially closed, these ‘better’ ones, but are totally different animals to the foams from the sheds. Cheap stuff is like crumbly honeycomb when set, and you can scrape it out with your finger, but the 330 is insanely better and when cured goes a lot harder / stretchier, and has far fewer voids in it. Been using it for years on anything which needs airtight / cold / damp bridging to be resolved. Use it all around my windows when they were changed, and damp disappeared and hasn’t come back, much better.

I believe I have spoken……

Don’t make me come down there and squirt you with it. Just do as the Welsh fella says, and use that one. Now “go” 👉

Illbruck FM330 mate. Use that, and scoop the other stuff out.

Once the air gap is gone, the condensation won’t form. Does the pipe have some sort of duct, or is it straight out of the ground?

Water will definitely track / sit all along the threshold, which makes it even harder to discover exactly where it’s coming in. The extra silicone outside is probably adding to the problem, as the water cannot escape. You either stop the water getting in, or leave it a way for it to get out.

You just need to put some thin insulation on the pipework. That is the solution here. Covering with a foil patch will just cause it to ‘sweat’, and that’ll harbour damp forevermore. The hole in the floor needs to be open to the room, with just some rockwool stuffed down it, so it’s about 50mm below the tiles, to prevent draughts. If you can move the stopcock then do so, as replacing to would be a painful job after you build a kitchen over it. You can ask the plumber to fix a 90° bend at the point the blue pipe exits the floor, and then convert the blue pipe to 22mm copper and then go to a new 22x15mm stopcock in the unit, with all pipe under the slab insulated and forgotten about.

The damp ingress is all the way under the threshold, from side to side, and that’s a big issue that needs to be addressed robustly. The cement that’s been put in the gap needs to be painted, then a frame / external sealant from that to the door frame to be weathertight. Also, there should be a piece of D section (referred to as makeup) over this joint.

It’s just the time of year, with lower cold water temp vs heated homes. The foil patch is the worry thing you can do. Just put grey pipe insulation (13mm wall thickness minimum) on the blue pipe and the copper pipe, and it’ll solve the majority of the problem. You’ll still get condensation on the stopcock, but that should be above the units not below, ideally.

Did the bigger patch on the right of the picture of the concrete appear with the first rain, or after the cement was filled into the vertical gap outside? That is the one that worries me the most as it’s a significant amount of water getting in and it’s quite far into the porch. Does it dry up if it’s not been raining? I’d guess this is coming in from either poor sealing at the side of the doorframe, or worse, damp being drawn up out of the ground if the damp course hasn’t been done correctly. Did you see them put a membrane down under the new concrete? My gut feeling is that this hasn’t been installed to be fundamentally weathertight, and the fitter isn’t very competent. I think the door will need to be removed and reinstalled properly, by someone who understands the job. Adding silicone etc is a complete waste of time as water is getting to the concrete under all of that cosmetic coverup. Also silicone is useless unless everything is completely bone dry, as it will not stick to damp or wet surfaces. This just sounds like you chose a poor fitter and he’s just not able to do this work properly. Good that he’s been back to try and resolve, but his efforts are clearly of no use.

Sadly, @joe90 has passed away. His profile remains as a legacy, and for its useful and inspirational content, as per his wishes.

If the rads need a higher temp to function, then you should be setting the CH flow temp for the rads, then the TMV on the UFH governs max flow temp into the floor. If the system is set up to service the UFH at 30° then the rads will be doing near nothing. They feel cool / cold as your body temp is higher, so placing your hand on it is a poor point for reference; the true reference is the actual temp of the room / space, so if the rooms at the desired temp then it’s all doing what it’s supposed to.