Bemak

thanks for this!

I recently came across 'over floor' heating systems which are essentially an underfloor heating system in a 30mm screed - the idea being that the system is much closer to the surface of the floor allowing for quicker response times while generally running at lower temperatures. I spoke to a supplier about it and they said the following which I thought was interesting "the system achieves a typical operating energy reduction of 50% daily compared to heating the same space using Under Floor Heating". "Conservation of energy on a daily basis sets the ground work for affordable heating and sustaining the building, the most significant feature of Over Floor Heating systems is the remarkable increase in comfort created by operating the system using water at body temperature". All sounds great. I'd be curious to hear of peoples experiences using such a system as I wouldn't be opposed to trying it on a refurb I've started.

just a quick query on a detail I want to ensure is correct. i'm planning to construct a cavity wall extension to the side of an existing two-storey farmhouse. the new extension will replace an old stone extension and we've yet to determine if the stone extension was keyed into the stone of the main house. In any case - I was wondering how best to detail the junction between the new blockwork and existing stonework to prevent any water in the stone wall from getting into the inner leaf (as per the crude diagram below). Is a vertical DPC the best bet or is there a better way of doing it?

that's a great point regarding the soak away in the middle of the run. Thanks Nick!

yes I was looking at something similar. An extra bit of lining in the trench like you say will help a lot.

its a personal preference to not see it.

Hi all, In the initial throws of a refurb at the moment and one thing I'm trying to bottom out is the location of the external boiler. The existing house doesn't really have a rear elevation - it's seen on all sides which is making it a bit difficult to locate the best place for the boiler (inside is not an option). I have a shed nearby that would be perfect, but it's 18m from the house. I appreciate that this is quite a distance, but just wondering if I did a deep trench for the pipework and double up on the insulation around the pipes themselves, would it be a viable solution? Just wondering if anyone else has located their boiler a similar distance from their house and what they did to minimise heat loss.

this is my project - sorry have been offline for a while. Just as an update, over Christmas I had a builder friend call and run through the plan of attack. In short, new floor slab with UFH - for the walls we're going to dry line internally with a metal stud set off the wall by 10mm or so. The insulation between the stud will be either a hemp combi jute, or gutex thermoflex. wall will be slabbed with a gutex thermoroom board on a finsa vapourstop. skimmed with a breathable lime render. when we reviewed the floor joists, they weren't too bad. any bad sections were tight to the external wall. so the metal stud approach will also act as a support for the existing floor joists.

Hi All, Hoping to kick off a project I posted about here previously at the end of the year. It's been delayed for multiple reasons but hopefully it will get a bit of momentum in the next few months. House is an old 2-storey farmhouse, 140 years old with 600mm thick rubble stone walls. The house is in good shape considering it's rarely used and structurally very sound. I had been mulling over whether to dig out the slab at all as the existing floors are relatively sound. In the end, I've decided to dig out the existing floor as it will allow me to install UFH, a radon sump and membrane, and insulation. I was talking to a very experienced contractor about it recently as I was concerned about the potential knock-on of digging out the existing floor. He suggested that I keep the excavation to the minimum and suggested a build-up of, 100mm compacted hardcore, blinding, Radon barrier, 150mm insulation, 50mm liquid screen with UFH. 300mm overall. his argument is that the existing subfloor would already be well compacted and that the suggested buildup would minimise the potential of disrupting existing walls. I agree but I just wanted to put it out there to see if anyone has done something similar?

ensure as well that there is adequate fire stopping between the bedroom and garage. I think it needs to be 1 hour from memory.

The alternative is two or three dMVHR units in the vents, like the lunos e60 etc, which would work in tandem to extract/supply air into the house. These look great for completely airtight houses but I'd be curious to know how they work with standard levels of airtightness.

Thanks Peter. Ideally yes but I looked into the ducting for MVHR but we can't make it work for the downstairs rooms. I appreciate that we would be losing the same amount of heat, but wouldn't that be distributed across the vents as opposed to one blast from a PIV system?

Ok so bear with me on this. Existing 70s house, semi-detached, two-storey. Typical condensation issues associated with a house of this nature. I need to core a few extra wall vents to improve ventilation but I was tempted to add a PIV system to help move air also. However my main concern with this kind of system is the potential for cold air/draughts etc. I'm also not keen on the heater element either as it drives the energy consumption way up. As an alternative would it be completely mad to have a extract unit in the attic do the same thing in reverse? i.e. extract air from the house from a central location (first floor landing) which would have the effect of pulling air into the house from "all the nooks and crannys" and wall vents (as opposed to driving it out). That way the draughty element is reduced as it's warm air that's being moved out as opposed to cold air being drawn in? Just putting it out there. Advice greatly appreciated!

ya definitely not a nice job. It means removing more of the existing fabric than I initially had intended too might be worth it. In my case it would allow me to install a radon barrier and sump also which is a consideration too. Good luck with your cellar dig - you're very good

Good to hear. No doubt there would be an improvement. I haven't the final price back yet so it'll probably become apparent quite quickly if it's a runner.