LA3222

I think the girls will like that - they have established a rule where only one of them can be in their room at a time at the minute (bar sleeping!). After a couple of years of this I am sure they will appreciate the space!

The outside skin of my sip panel rests on an EPS upstand so what gives? I give up - you can't/won't see that the point I am trying to make is when you talk about sole plate issues you speak as if it is a SIP only problem and a negative against that particular method of construction. The way I see it, a soleplate is a soleplate, so with SIP or 140mm stud wall you have the same issue. The difference lies with timber construction which have the loading on an inner member such as Larson truss (being the most common as that is what MBC use for their passive construction) - but I am not talking about them. I am talking about 140mm stud walls and SIP. I think the wording of your advice regarding SIP is at times misleading in that the issues you raise are not unique to SIP but your wording perhaps can be construed as implying that.

So can we agree that the soleplate issue exists for all TF construction bar Larson truss type methods.

Ha, ^this ^. The summer has been honking in the van, to the extent that I spent £350 on an aircon unit. It's not entirely effective as I had to MacGyver the outlet pipe onto on of the vents along the bottom of the van so some of the hot air leaks back into the van and the pipe gets bloody hot further bringing heat back in. But it does make a difference at lowering the temp down a few degrees but it needs to be used sparingly. I have a dehumidifier on the go 24/7 to try and eliminate dampness. The van came with wall panel heaters in every room and I bought another couple to go in the lounge and missus room. The kids share so their room gets hot. Once the house is built it will be strange having so much space again!

How do you do this with a 140mm stud wall?

Glosford. I note you mentioned SIPs ECO which is a slightly different type of SIP. IIRC they bond EPS panels to the OSB skin, slightly reduced U Value so potentially thicker panels required. The type I intend to use have liquid PUR injected into them which then expands and bonds with the wood. Many ways to skin a cat. I spent a long time dithering on whether to go with Glosford or Fleming, I found MBC to be pricey but it may be that when the dust settles MBC aren't comparatively much more expensive. I'm normally decisive but this had me going in circles as so difficult to choose. There are so many variables to consider such as what time of your own can be put into the project. Glosford sat in the middle between Fleming and MBC price wise so I went with it - I also prefer a SIP roof as it gives me clear space in the attic with no trusses to negotiate around. I am similar to yourself, 37 with an 8 & 9 yr old. The missus and kids live onsite in a caravan whilst I live down south during the week so them being onsite helps as I go 'home' to the site every weekend and can work on the build. The downside is they have to live in a caravan which will likely be grim come winter. I sat the kids down and discussed the choice with them and they all wanted to be there and they are mentally prepared for up to 2 yrs like that. You can save a lot of money by doing work yourself but it's never free, you'll have to sacrifice time with the family to do so. I'm sure that like the rest of us on here you will look at the bigger picture and know it will be worth it in the end. Wish I had 3.8 acres - I have 1/2!!

Also, apologies for jacking your thread @SuperJohnG, you will find they can take on a life of their own!. Good luck with the plot purchase?

As an aside, you mention The design TSD did for me has the inner bulk of the soleplate on the slab with the outer bit sat on insulation - abeit only about 40mm thick at the top. Not sure how this performs in terms of heat loss as a thermal bridge!!?‍♂️

So, what I take from that is a twin stud is different (as I already knew). But a 140mm stud frame (The majority of TF) sits on a 140mm soleplate in the same way that a SIP panel does - so the problem applies equally to both? There is no inside/outside member for 140mm stud so it is no different to SIP sitting on a 140mm sole plate. So when you comment about SIP being subject to interstitial issues it is misleading as the wording implies this applies to SIP and not others when in reality it applies to most TF structures?

Welcome, this forum is an endless font of useful info and im sure that like myself, you will find it a great resource. I too am building with SIP. I have my foundation design from Tanners and the SIP design done. Pulling it all together for building regs. @JSHarris you are at it again - Surely this is equally true of standard timber frame construction (as I understand things?‍♂️) as well as SIP. Your comment portrays it as a SIP only problem and paints SIPs in a bad light relative to other methods of construction. Yes I get this problem exists u like with your own 'Larson Truss' method but it is not unique to SIP. If I'm wrong then I will eat humble pie, once I understand why I am wrong ?

Exactly the reasons why I went 3 phase - I was dancing on the edge if only went single!

I suppose it's all a matter of perspective, I can only assume you are 'downsizing' from a 12 bedroom manor complete with tennis court ??

That looks massive! Out of interest what is the sqm? If I recall correctly, you have a basement too? Looks good ?

That GMS building was looking in pretty rough shape when I ran past it - looked like it ain't been used for years. I did see a couple having a wander round, looked like potential buyers - maybe to renovate or knock down/rebuild. Very exposed position.

It's something I had yet to turn my mind to tbh @JSHarris. I have been in contact with Wunda ref UFH as I will need the pipe soon to put into the slab and they asked what I would be using. I remember reading that SunAmp can be used for DHW and space heating hence the query. Your answer settles in my mind that it's a 'pump' idea which suggests that in a house that doesn't have gas the ideal setup is to leave SunAmps to the DHW side of life and an ASHP for the UFH.

I've had a scoot around for the obvious and can't seem to find a thread where this is covered. So my understanding is that the current crop of SunAmp's can be used for domestic heating, my query is can the UFH run directly from the SunAmp and if so how/has anyone done this yet. I assume that if the SunAmp were to be directly connected to your UFH it can't be used for anything else then - it is forever more stuck supplying warm water to the slab, so there is the cost implications there. Also how would you size it appropriately? If your peak heat loss is 5kWh and you bought a 5kWh SunAmp it would be depleted after an hour, or would it charge back up as you use it? So do you then have to oversize it - double, so 10kWh? I intend to make use of a large amount of solar and intend to use SunAmp's for my DHW, I'm just pondering the best way to approach the UFH. Is it a case of an ASHP is a better fit for the UFH? Sometimes, although something 'can' be done it probably shouldn't - so am I barking up the wrong tree here? Thanks

? I agree they do and I think the walls do as well to be fair. In my head they have much the same issues as a standard TF which has studwork at 600 centres - just less of it. However SIP cost a lot more so they may not be cost effective to take advantage of the reduction of full thickness timber within the panels ?‍♂️

Sorry, might not have been clear but I meant insulate under.

Your roof is a better design @JSHarris and I don't disagree with you. I'm picking really at your original comment which can be read as suggesting SIP suffer more from thermal bridges than a.n.other type. If you look at it from SIP compared to truss with insulation between the rafters then there is more insulation present in the SIP one and therefore better U value? (Disregarding cost comparisons)

Can you not add an internal layer of insulation to eliminate any cold bridges? Much like you insulate under the rafters of a truss roof?

I would argue that there are significantly more thermal bridges with a truss roof due to far more timber being present? So why are SIP portrayed as worse? Surely they are an improvement on a truss in terms of a reduced amount of timber being present?

Cheers for the steer @Russell griffiths. The slab (till the concrete pour) seems a simple thing to do - just getting the how straight in my head so I don't have to make things up on the fly once I start.

It occurred to me that I may be able to get the supplier to chop it up for me - not sure if they will. The 4.8x2.4 sheet is useful as I need 0.6 wide lengths in the bottom of the thickened perimeter strip so that's the 2.4 sheet cut into 4 strips which would save a lot of work. Most of the other bits will be full sheets.

Good point there Peter, I had overlooked that particular issue. A393 is specc'd for the thickened parts, A252 throughout the rest of it. Need to work out how to cut it - likely an angle grinder which will be time consuming!

There are three areas - two are steel posts and the other is just an area where the point loads have worked out high for whatever reason.