Owain1602

I'm not sure if this is new (it wasn't on the Catnic website six months ago), but Catnic has a system called SolarSeam. https://catnic.com/products/urban/solarseam No personal experience with it, but I'm considering it for our build.

@Glenn thanks for your input. No need to apologise, that is the whole reason why I asked for feedback on the layout. I have a feeling in the back of my head that what we have isn’t quite right. You are right about the fenestration, I specifically mentioned this in my original post. We have options to centralised plumbing further, but I don’t want to compromise on room layout for the sake of running a few plastic pipes.

@MR10 I have discussed this with ETC in the past (before I was comfortable to share the plans openly). He had some great ideas, but it was so different from the design we’d had in our head, that I couldn’t really process it.

Thanks for your messages @AartWessels and @Glenn. These are plans that have been put together by a well-respected architectural firm. Whether they’re being hamstrung by our requirements, I don’t know. But as you can see, we’re not asking for too much in such a large space. Do you think I should instruct another firm to take a second look at the design?

Thanks @AartWessels I don't agree with your logic: we can easily find space for everything, for example, I could have a 25m2 plant room and the job is done. But it's not the optimal solution for us (it might be for someone else).

Forgot to mention @JohnMo, the idea about marking it out at the beach is a great idea! Having looked at swapping the plant room and downstairs W/C such that the ASHP pipes could come through the wall. I think it results in the same issue as the original location if I've then got to install a duct under the floor to bring the pipe to a more central UFH manifold, after they've come in through the wall for the HWC. What do you think of this proposal for positioning of key components. I've assumed dimensions for a large Zehnder Q600 MVHR unit, HWC with ⌀700m, with a ⌀1000mm for working area around it. We should be able to easily achieve a separation distance of 2m between supply and extract of MVHR (sketched them closer for drawing clarity). From reading other MVHR posts, it sounds like having the external vents somewhere other than the roof is a benefit when they need clearing out regularly during the spring and summer. Presumably I can install a large distribution box/plenum inside the posi-joists of the first floor walkway (shown by red rectangle) such that the lengths to/from the rooms is more balanced? Would then have a run of ~6m of rigid pipework between the MVHR unit and the distribution plenums. I'm going to contact BCP and 21 Degrees for designs and quotations shortly but I want to make sure I'm giving them a reasonable starting point with the room layout. I think I also want to turn the pantry in to a storage cupboard, for stuff we don't need frequent access.

Thanks very much for your interesting comments, some useful points already. First, to @JohnMo's point regarding fire spread. Do you think we should look at properly closing off the kitchen/dining area with a wall like I've drawn in blue? Would also help with reducing spread of cooking smells etc through the rest of the house (as a secondary importance of-course!) I see what you're saying about the storage, but we were planning on having storage built in to the office and playroom. For the ASHP plumbing, on the other side of the wall next to the W/C is where the ASHP would work, since it's by where the cars will be parked. So we could consider swapping the W/C and the plant room. If the underfloor heating manifold was to be placed behind a cabinet in the boot room, could I run the feed/return lines through the first floor posi joints from the new location of the plan room? Or would you put a duct in during the slab pouring? Must say that I'm struggling a bit with the MVHR. With it being a barn, we have a shallow roof pitch, so it doesn't naturally create a typically generous loft space. Plus I assume it might be best to not place it directly above a bedroom from a noise perspective. To the other points: @IanR Yes, it will be a "thick" timber frame, probably going with the twin-stud system. I had indicative quotes about 6 months ago from a lot of the main suppliers (plans were very similar to this), and the twin stud wasn't as much of an increase as I'd feared. Same as my note about regarding making space above the first floor for MVHR and other bits. I think the whole height attributed to the roof pitch is 1,600mm over a 6m width. Perhaps I could put a ceiling on the bathroom between bedrooms 3 and 4. The void created would be about 1.3m at its highest and 0.5m at the lowest side (with reasonable ceiling height in the bathroom) Then @Blooda I'm slowly trying to get rid of the pantry, definitely not my idea. If I could convince you know who that we don't need a pantry, then it would free up a bit more space for the MVHR to be downstairs an fairly central along with UFH manifold and extra storage cupboard. Like your idea about the guest suite becoming family bathroom with two entrances, will definitely look in to that. Bedrooms 3 & 4 are for our two young boys, so a Jack and Jill type is not an option unfortunately. Our idea was the the eldest would get this bathroom and the youngest would use the guest bathroom once he's old enough, since that would only be used occasionally by guests.

Hello, we were granted approval to "upgrade" our existing Class Q to full planning on our barn conversion a couple of weeks ago. Now that has gone through planning, I would like to share the plans and get feedback from people that have actually done this, and have experience how numbers on a page turn out in reality. Plus, there might be things we can do with the design now that makes things a lot easier down the line. The build will be a timber frame construction with a passive slab, standing seam roof. There are a few caveats to the plans shown below: Barn will be ~300mm taller than shown in the elevations Fenestration is a bit of a mess (needed to get plans submitted quickly as we had a potential issue with Class Q expiry, they were very much a submission to establish the principle). We will apply to change these with a NMA once we're all set with the layout Please ignore the portal steel frame in the plans Some points which I've just started to think about: Is the plant room big enough (house will have ASHP with underfloor heating, water cylinder, MVHR, not very bothered about smart tech) Can I duct the ASHP pipework out underneath the slab such that the unit itself can be positioned on the North or East side of the house (plant room is next to front door and I don't want an ugly unit right outside the front door) How could the MVHR be positioned with the inlet/outlet to external? (Will be contacting an MVHR company to design the system shortly) Really looking forward to hear any feedback you might have (not sure I have the headspace to consider a complete U-turn with the layout though!)

Thanks for the replies, I thought it was all good news but wasn't sure if there was something I was missing. @JohnMo That is a great site you have. Can't quite make it out from the pictures, but do you still have a large slope leading down towards the house from the back? If so, did you put any drainage provision in for water coming down the bank? @saveasteading I think I will put some form of drainage pipe behind the retaining wall just to encourage the water around the house Maybe for another thread, but another question that comes to mind with a slope is, can you have too much slope on the foul drains leading from the house to the treatment plant? I'm aware with some drainage that too much slope means the water/liquid travels through the pipe too quickly, leaving solid material stuck.

I'm not exactly sure what my question is. The barn which we'll be converting is positioned in a field which has approximately 2m elevation change across a 40m length. The field slopes down towards the barn, but continues to slope away beyond the barn, so it's not like a bowl. We'll need to dig out the highest side and create a retaining wall (~1m high). This got me wondering what the concerns are when digging in to a bank, particularly with regards to drainage of the fields above the barn/retaining wall. The site is one of the highest in the county, everything slopes away from us, and the ground is said to be very sandy and remains dry all year round. I presume the concern is that heavy rain could saturate the ground, causing further rain to flow downhill along the surface of the ground (a river). This must be a particular issue for poorly draining soil (such at clay), where the ground becomes waterlogged due to water not being able to freely drain downwards through the soil. But with very sandy ground, could this still be a concern? As a slight aside, we have a long 1m high retaining wall (rail sleepers) in our current garden with the entire garden above the retaining wall sloping down (1:10 gradient). We have never seen any water coming through the sleepers.

Thanks very much Alan. My understanding is that self-build exemption does not apply if the site area is greater than 0.5 hectares. I'm interpreting information from here: https://www.gov.uk/guidance/biodiversity-net-gain-exempt-developments

Hello all, I've been a member here for a while, trying to learn as much as I can from reading any mildly relevant thread. We recently purchased a 5 acre plot of land in open countryside, on the land is a barn which has approval for conversion under Class Q (expires April 26). The ideal scenario would be to build an efficient timber frame house on a passive slab, after demolishing the existing portal steel frame (current barn does not have a concrete floor). We put in a pre-app to demolish the steel frame (keeping to the original footprint of the barn), and were told the local plan has policy that Class Q approval is not considered a fallback for a new-build dwelling, as such, it would not be supported (although this policy does not appear in the new emerging local plan!). Our architect spoke with the planning officer, and discussed the idea of wrapping the existing steel frame within the timber frame (means extending beyond the original footprint by ~350mm), and apparently was told that this would be supported via a full planning application. So here we are, finalising details of our full planning application, which now needs to include the full BNG calculations and report. The deadline for needing to start implementing the existing Class Q is fast approaching, and if we're knocked back with this full planning application, we'll need to resubmit for Class Q (under the old regulations, before May 25) which should restart the 3 year clock. I have been an engineer myself for nearly twenty years, technically leading projects in the automotive, formula one and aerospace industries. My background was originally in numerical simulation of combustion thermodynamics (CFD), but now work on a fairly broad range of topics related to high voltage systems, battery thermal systems, controls and algorithms. Don't ask me anything about a domestic heat-pump control system though! Nice to meet you all, I'm not sure I'd have the confidence to embark on what we're doing without the invaluable expertise and experiences I've read about on this forum.