Sue B

Thanks @PeterW - 5days to watch

@JSHarris - have you got details of your surge system please? Yesterday my little Smart car nearly floated home as our drive was a little submerged.

No we don’t but they are so stable and easy to use, was thinking a reducing scaffolding need as we built.

@Russell griffiths - just had to search to find this thread. I know that you have bought the scaffolding and are planning to sell on once you have finished your build. Did you end up buying the bracing as well - Peter and I just can't remember what you said when we were on site. If so, was the bracing the one you were talking about above (zonts and zuckles) and have did you all go ahead with the agreement to sell on to each other for a 3 way split of the costs?

We use a large amount of water as we have large koi pond which ‘im indoors likes to partially empty and refil every few months. We also have a large kitchen garden which requires a lot of watering in the summer. We were intending to install a rainwater harvesting system. However, the 2 people that we know that have them, have both had continual problems with them. One has needed a new pump every year, the other just gave up trying to keep it running. We have decided that when we have a digger on site, we are going to dig a well that he can put a submersible pump down, to water the vegetable garden every night. The well will be in a shed that we can keep locked so that it is safe.

VCL was mentioned during the Durisol course but I didn’t listen as I was busy making notes about another issue and it was just background noise at the time. However, I will of course be asking Jamie about it later this month during the Isotex training. Heads up Jamie - you know one ofnhe questions coming your way ?

One of our wish list items is wet plaster (possibly spray) as opposed to dot and dab. Partly because of the air-tightness but more because I just prefer the finish.

???

Not far at all @Adam2. I was in Poole this morning and took the opportunity to drive round past the Durisol build there. Window forms are in so I'm sure they will be pouring very shortly.

I think that I definitely heard that . Does this lead to pistols at dawn ? Please, at least let him finish the bathroom first ?

This is what is was thinking of - not you @JSHarris but @najem-icf. “Reminds me of an article I read when I was Stateside some years ago about a Durisol build 22 storey hotel in Canada - built back in the early 1980's - guests complained of "ghosts" in the rooms - later realised it was curtains moving due to air penetration through the structure.” I knew I’d Read something somewhere.

Hopefully others will find it useful, the danger is that it will be too dry as it is my decision making process as opposed to nice action posts - that should, with luck come along later.

But I am FANTASTIC at Lego ?? It’s not the strength but the air-tightness that I think will be different. I know that @JSHarris has previously mentioned that concrete is not necessarily air tight but it has a much better chance than the woodcrete. The difference between the three products is how complete the concrete wall within the formwork will be. During the Durisol training, they were very keen to talk about the product being breathable. Passivhaus and air-tightness were almost dismissed as a goal not worth aiming towards. The MD (a structural engineer) went so far as to state that it made no sense to him as an engineer to make a property air-tight and then introduce an MVHR to bring in ventilation. They also talked about Thermal Mass and I just smiled sweetly and thought of our Jeremy ?. We went to a passivhaus seminar at NSBRC in November and cat flaps were mentioned. IIRC they were mentioned in the hundreds of pounds to much laughter. During the Durisol PowerPoint, a similar cat flap story had become thousands £s. We have a similar story in our family. Peter lost £5 in the sea in Cornwall during our first holiday together when we were mere babes. (17 &19). This was way before children came along and before the lottery existed. That £5 is now referred to by the kids as a winning lottery ticket that would have set them up for life if only their dad hadn’t lost it in the sea - it has taken on a life of it’s own ??.

When we first started on this path, we wanted a hands off, almost turnkey project. I'd heard of SIPS and seen lots of positive stories about energy efficiency so all was set. Then we spoke with a mortgage advisor and our world started to tumble down. I am now 56, Peter is 57. We will need a mortgage to build this house but because of our ages, we know that the mortgage providers will all keep the term of the mortgage down to 15 years max which will make the repayments large. Drastic action needed to be taken so we have now decided to build using a method where we can do this ourselve. We have no experience of actual building work but let's face it, how hard can it be ? - famous last words. Our previous house was built using traditional methods. We did have underfloor heating and a MVHR system but we struggled to get through the air-tightness test. We have learnt a lot since then. We nearly built that time round using ICF but I chickened out. This time, it looks like it is going to win. We have looked at the various types of ICF. The majority are of course the polystyrene type blocks and these do have real advantages for self builders. They are light and easy to manage. Our main issue with them is the fixing ability at the end of the build. Once the plaster is on, finding the fixing lines becomes harder and harder and so other ways of fixing heavy items to walls need to be used. Looking at various websites and you tube videos, it is also apparent that blow outs are more likely using the polystyrene and more bracing is required during the pour. The concrete is of a stiffer consistency that with the woodcrete ICF. The woodcrete type ICF blocks solve the fixing issues - you can attach anything to it. We have looked at three types of this type of ICF, Velox, Durisol and Isotex. Each has pros and cons and we have yet to decide which type to use. All three appear less likely to blow on pour day without significant bracing but of course it can still happen. We can't get a price without plans so at the moment the comparisons are being made purely on preference but without the benefit of a cost comparison. The concrete for this method is of a very runny soup like consistency. VELOX This method uses two flat panels that are clipped together as you build. The panels are large - 2000mm x 500mm so will go up quickly. One panel has the insulation attached to it. The system comes with a variety of options for the depth of the wall giving different u values. I have found getting information from the website quite difficult - the website is clunky and parts of it are not in English. The way the panels fit together, you end up with a completely solid concrete wall inside the formwork. I believe this gives a better chance of airtightness from the actual structure of the walls. The UK supplier seems to be a little difficult to get hold of sometimes - maybe this is the result of too many enquiries but it does ring alarm bells to me. The system has products for both internal walls and floors. The internal walls are two panels glued together, this takes the weight to 68kg - we struggled to lift a panel off the floor so raising it above shoulder height would be impossible for us. The size and weight of the panels pretty much rules this system out for us as it is simply too heavy for us to manage ourselves. It is however, my favourite product. DURISOL Durisol blocks are more like a squarish 8 with the top, middle and bottom bar at less than full height to allow a honeycomb concrete wall to form during the pour. The blocks are all 500mm x 250mm with the external walls coming is two depths - 300mm with a u value of .23 or 365 mm with a u value of .11. There are 3 different types of blocks. A standard block with the reduced internal height connectors. A facing block which has one end at full height - this is also used for lintels. A corner block for ...... turning corners! Because of the way the blocks work, the second row and above will all need a cut to ensure that your keep the "brick bond" in place. This is particularly pronounced if you choose the 365mm blocks as it is the width that causes the issues. QUESTION - couldn't you fix the problem by making the cut on the first row instead and increasing the size slightly so that every other run works properly? That didn't cross my mind at the training. The blocks have male and female ends so that they lock togehter prior to the concrete pour The blocks are rough and gloves are definitely needed. The blocks do shed while you are working as well so care needs to be taken to butt the blocks up properly as the debris can move things apart a little. The design of the blocks means that there are the 3 woodcrete bars, each end of the block buts together with only a small amount of concrete bonding the blocks together. The blocks are produced in this country so less likely to suffer with issues to do with Brexit. Lead time is in weeks. Free training is provided (we have done the one day training course) and they will come to site to help you get the first row laid, ensuring that you get a nice level row. Purchase of the blocks over £10k gives you one free site visit (need to check if that is the initial row or if you also get the first pour day). Other visits are by negotiation but they rely heavily on facetime calls to see your site without actually being there. The anecdotal evidence that I have is that Durisol will discount heavily but they do not talk about a standard price - you only appear able to get a price from the drawing that you provide. I believe this will be our third choice of block based on properties but is probably the cheapest of the three. It is also the one we are most likely to use due to the price. ISOTEX Isotex is a very similar produce to Durisol. The blocks are mainly 500mm x 250mm but there are "pass" blocks to match the block depth that you have chosen. This gets around the issue of "brick bond" issue. The blocks come in depths of 300mm with a u value of .23. 330mm with a u value of .19. 380mm with a u value of .15 and 440 with a u value of .11. There are more options for shape of block - not sure how much that will help on site - will it be more difficult to find the right type of block while doing tricky areas? The shape of the blocks is like an H but with 2 horizontal bars not one. This means that the blocks allow a freer flow of concrete between the blocks than you get with Durisol. It will still be a honeycomb but less so, there is roughly a third less woodcrete in the way of the concrete wall. Butting the blocks together mean that they just sit together without the benefit of the locking togethre - this means that there are two short unsupported parts of the block holding the concrete - does this make a blow-out more likely? Insulb the UK supplier provide similar training to Durisol - we are attending in February half term at Swindon NSBRC. The blocks are slightly smoother than the Durisol ones and seem less likely to shed. Jamie has made it quite clear that the price is non-negotiable. £55m2 for the 300mm block (I think I wrote down the correct block size but not 100% certain) against £62m2 for the 440mm block. I believe that this will be our second choice block based on properties and probably second choice one price comes into play - time will tell.

Thank you

I am thinking about doing a blog - how do I create one on here please?

The passivehaus seminar we went to at NSBRC late last year talked about blinds to counteract solar gain. Their advice was blinds have to be external to be effective. Even blackout blinds internally let the heat in to the house which then has to be dealt with. From memory the percentages were 98% effective if outside, 1 or 2 % effective if inside. I was hoping that they would send the PowerPoint slides but they never arrived. I will try today to see if they will share as there was info contained in there that would be useful to review at leisure.

That sounds like a good result - well done

At the Durisol training yesterday they stated that they were in the process of applying for BBA 2 (whatever that is) but don’t have it yet. There also appears to be an issue if your warranty is with NHBC. They glossed over both points but I did question both but and my notepad is at home where I wrote the notes Of their response. At points, I thought I was the only one asking questions and thought the other people were going to start throwing things at me!!

I think you’ll find that providing a toilet on site is expected if not a requirement. If you don’t have a toilet, I’m sure they will make do, somewhere ??. i have a feeling it is part of the CDM regs??

Could be Jeremy although I think you can probably understand our reluctance to try again. It was 10 years ago and things have moved on as well.

When we built our first house in 2008 we bought an add on for the MVHR system for comfort cooling. Our electric bills shot through the roof the first year we used it and we noticed no cooling effect at all. I wouldn’t buy again. Visiting MVHR stands this time round, when we relay our experience, the experienced suppliers nod sagely and agree with our findings. The same with the central vacuum systems. We wouldn’t bother again but I love the idea.

I would love to have that but just can’t get it in the plan. A precious version had our kitchen at one end of the house purely to allow this type of larder arrangement. Maybe i’ll give it another go. I was always very jealous of MILs larder that had an 8inch window frame, no glazing but a wire mesh in the larder. It was lovely and cool.

There is an Isotex build going up in Leatherhead very shortly. I have asked if we could be there on first pour day to see how it goes as it is commutable for us. When we asked about bracing, we were told not that it is not needed and that the pour should be every 6 rows so that matches the sales information that we were given. I can’t see why BBA wouldn’t be forthcoming but would expect the structural warranty to insist on it anyway before we proceeded (regardless of how useless much accreditation appears to be). Therefore i’m not going to worry about that yet and assume it is going to happen until proved wrong.

We are going to the training day at Swindon for Durisol this week, we have just booked the equivalent day’s training for the Isotex system in February. Both courses are free and available without purchase of the product. Happy to report back on pluses and minuses that we find once we have been on both.