MikeSharp01

Yep!

Hi @ProDave. I see you are using the Protect Barrier membrane - I think I see it at work in some of the pictures, is that the one with built in sealing tapes and if so how did you get on with the in built sealing tape?

Thanks all - very interesting, looks like I may have to rethink a little. I guess I can ensure that the kitchen sink is not used when the shower is in use so that will help. I think mains water is about 6 degC so that plus 28 only gets us to 34, not enough for a shower. @Nickfromwales if I go for a small unvented cylinder won't I be in need of part G sign off which I had hoped to avoid or is there some sort of low volume limit? In my original thinking I was considering using an electric shower and an inline heater but I figure, @recoveringacademic I have not found the Stiebel curves either but based on what @JSHarris says, that I would get a pretty poor flow rate from the shower units as in the end the basic physics must limit the flow / temp / power curve. I can squeeze the 12Kw Stiebel model, 11Kw at the expected voltage at the end of the wire, which will give me a calculated 32deg rise at 5l/m. To get to 40 degC and assuming the linear relationship Jeremy describes 4l/min does it. So if I interlock the sink tap with the wet room lights via a solenoid valve I can perhaps get all I need from the Stiebel unit.

Just working out the plumbing for the 30 m2 garden room (GR). Small sink, washbasin and shower. To keep it simple I think an instantaneous water heater should be OK for the job. Reading here ( @JSHarris ) and elsewhere the Stiebel Eltron DHC-12E looks like a good bet (£202 on Amazon). There are a couple of issues firstly the unit will be 45M, run, from the Electric meter, 16mm buried in ground comes out OK and because the unit derates a bit, assuming I have read the blurb correctly, through voltage drop I will have a few amps to play with on the 63A consumer unit for lighting in the GR when the unit is running. The second complication is that we, note the use of the word we, would like the Stielbel unit in the cupboard under the sink, I cannot see a problem with this as the brochure shows a unit, or very similar, under a work surface and hopefully most of the heat goes into the water and so it won't warm up the cupboard too much. The big question is can the Stielbel unit feed a thermal mixer shower tap, many of the cheaper units say they must not be connected to such devices but I can find no mention for this unit, or should I just set the temperature output of the Stiebel unit to shower temp and run it straight or use a manual mixer?

Thanks Dave, I am sure when I signed up the rep said I could see prices on-line, maybe not. I will call them in the morning and see what is what. I have Jewsons account and that shows me prices now.

Quite a lot there. When we did our Garden room I went for 150mm of Type 1 +/- 10mm across whole surface - done in three layers and whacked each layer, then a 50mm layer of pea shingle +/-5mm (Quite hard to measure so what I did was lay two 50mm thick boards, one each side and get them level +/- 2mm and used them with a third board, actually one of our I-Joists, to scrape the pea shingle level. Then I created a frame into which the EPS sat and got the top of the frame level +/- 2mm get the EPS up to that and used the top of the frame to level the concrete. Then power floated it. Got most of it, 95%, it +/-2mm but one area was to wet when we floated and I dig a bit of a dip -6mm worst case so I have +2 / -6 as our finished slab (8.5m x 4.5m). Most frame builders want the slab level +/- 5mm. I got the final all flat level (+/-1mm) with the soleplate and some shims (Which you can only get in 1mm increments so I used some commercial plastic sheet at 0.25mm) and cut it up. Having done all that I won't be going to such close tolerances on the main house because the timber moves, shrinks, warps etc, much more than this error so +/- 5mm for me when I do that.

I must be missing something but, it might be the wine but I am blowed if I can find Howdens prices on line - I have an account and I can log in and look at invoices etc but there does not seem to be a place on the Howdens web site to log in and see prices. What an I missing?

PS they have been great to work with as timber goes but you have to store them straight, upright and flat. I made a 10m stillage for them which has kept them well but one I pulled out and left for a couple of days draped over the saw bench took on a very pronounced bend.

I am using the last of my first batch on our garden room. I got them through Jewson who were slightly more expensive than my local supplier but only by a fraction and they said they would crane them off. In the end the lorry arrived without a crane so I could have got them from the local supplier. The cost was £1260+VAT for 28 x 10m of 195mm joists delivered in Kent. On the house the SE has asked for a different make so I will have to find new prices.

Are electric milk floats still a thing?

I don think it will blow over. IIRCC (and I was only a boy when Dad built it) each pier is built around 4" stainless steel column sunk in the foundations. Plus we don't own it and I have not lived there for 32 years but I keep a watchful eye on the house that Dad and Mum built.

What about brick piers every so many cm then fence between them leaving a gap as @RichS suggests. It will look great and last a very long time. Downside may be cost. Here is pic of idea as my dad built 51 years ago - same timber. (Cedar) https://goo.gl/maps/9nmr4AoLN9z

Great partner essential. Sharing the details, the budgets, the decisions, the pain all vital. Partitioning the workload critical, when both are involved, what is yours and what is theirs.

Ah - thanks @jack I get it now.

@Onoff not clear what you mean. By knocking down I mean leveling to the ground so you end up with a blank canvas allbeit in its old context.

+1 for buy a wreck, knock down and build your dream.

In the end it will come down to the debt equity ratio you can stand. In the sense that the size of the mortgage you can get will depend on how it is secured. So the more equity you have in your various properties the more you can borrow against them, provided you can pay the mortgage. In this way you might get enough to buy the land and do the build then sell up and largley, or perhaps wholly, pay back the mortgages. The challenge with self build mortgages is managing the money as you go because you only get the payments against the equity you have built up in the property you are building. So if you can get the money against your current houses you don't have that problem.

Welcome @Babybirddog. Sounds like a great project and you are forging ahead just perhaps not at the pace you wanted. Things do take longer than you imagine in this game. I think you can rely on your fellow self builders here for support throughout and we will look forward to seeing progress. PS can see why it might have been forging ahead but where does babybirddog come from?

Why not investigate a dry stone wall just a short jump from pic J, perhaps expensive but the rocks will last forever, building it will be very therapeutic, no cement so other then the digger diesel getting it out and the lorry to haul it to you almost carbon zero and it can be repaired very simply.

I think @recoveringacademic is doing something like this is the link.

I guess that is progress of sorts, might it be worth checking the SEPA process to see if there is any consultation process or stakeholder comment scheme?

At the moment I am not sure, have not done the detailed work of calculating, of the economics (thermonomics) so I was keeping my options open to allow a system that could use either so it could choose at time of use which one to use depending upon the conditions / energy costs of each source at the time. The ASHP should do most of the work but there may be times when it cannot run at a high enough COP and the cost of gas gets under the curve and we use that. I don't like the buffer tank idea, because of the standing losses but provided the total heat output is used in the control calculation I am optimistic that it could be made to work. This not the least because I have a feeling that we will shortly be facing variable electricity pricing which could change the the thermonomics on a minute by minute basis. As things stand our design demand points are the UFH, DHW and an air heating battery in the MVHR system with PV, ASHP and Gas Combi as our prime movers, (me and my other half as the other, not so prime, movers) so getting these to all work cooperatively and optimally is the design goal I just need to work through the detail.

Yep. Looks like we will also have ASHP for UFH am working on how to make the UFH run from both sources.

Hey... We are contemplating a 35Kw boiler in our passive house for on demand DHW so 30Kw does not sound out of line for a semi.

Spent the best part of last two days, when not raining and or trickling my life away here, on the garden room roof. Came to realise that my tool belt, sturdy as it is won't take two nail guns, nails, knife, pencil, stapler, staples, hammer and a sharpie without falling down, albeit slowly. If you have one nail gun then it kind of jams as the load is all on one side. Anyway I have concluded that I probably need some braces. I have looked at many on-line but thought it would be good to get the collective experience as it were. Any polite suggestions?