MikeSharp01

Just been to one of the two possible window suppliers and now I know why the tape is there at least for this manufacturer. Essentially, as they explained it to me, it is set back a small distance to create an air gap up the side of the frame to ensure that the ali cladding can breath otherwise moisture would build up behind the ali cladding and not be able to escape. It seals the frame but is not designed to take up slack in the construction because the brakets etc still have to be a slide fit. If you clad / render up to the frame then you have to leave a 2mm gap to allow the alu cladding to breath. A bead of silicone would seal the gap and cause eventual failure of the timber frame. They also told me that it's life expectancy was 25 years, guarantee is 15 years so suspect it is the stuff @Nick describes above, in the open if protected then it should last much longer. Well that is what I was told!

Why such big gaps? Why is it not possible to make the windows a snug fit in the brick formed orifice? Such large gaps also have the visual effect of making the frames look much bulkier than they need to. @pauldoc I cannot find any life length guarantees on the tapes I have looked at so suspect they won't last unless mechanically protected from UV / Weather etc as if they did have a guaranteed life then it would be in their technical manuals / general advertising. In the ads for the product they show them as very much more compressed than in the @readiescards example also they show them mid frame so that sealant has somewhere to go to cover / protect the tape.

Cripes and I thought star trek was science fiction when all while the local builders merchants have been teleporting stuff all over the district.

Uh oh... Have not invested yet as I have borrowed a friends paslode which does a good job. The SE has not specified the nails only the spacing. I will ask for this detail. Thanks for the heads up.

Your are correct 5&6 is very much optional but as Kevin McCloud said when filming a friend of mines grand design 'if i was spending a million pounds and I was not confident of my capabilities I would want to be shackled to somebody who knew what they were doing' or some such. There are many building warranty suppliers and they have been discussed elsewhere on this forum eg here:

The Build Control Officer (BCO) they have to inspect the work, ensuring your building is built according to the building Regulations (BR), as you progress. You only need the architect to inspect the works if they are offing the structural warranty (they may not be cheap and they may not wish to anyway). You can buy an insurance backed warranty that takes the BCO's inspections and gives you a warranty for the building. The architect will need to prepare the full plans, all the detailed drawings, which includes getting a structural engineer (SE) to do all the structural calculations. The architect is responsible for ensuring that the design meets building regs at this stage, but things can change - see below. These, full plans, are what the BCO will approve, before you start, and then inspect the work at various stages along the way. The architect is only needed, if at all, after the BCO gets stuck in to resolve issues you find with the detailed drawings. Changes which affect the structure and / or any of the building regs will need to be agreed with the BCO as you go along. Hope that helps.

This is the structural warranty and comes either from an architect or more usually through an insurance product linked to the BCO scheme you choose. The architect (B) might not want to provide the warranty because their indemnity does not cover it. There are loads of companies offering structural warranties so hunt around. Make sure you get Architect A to releases the copyright to the drawings before moving to architect B.

Or watch last evenings 'building the dream' where a £5K budget for services ended up costing north of £40K! PS Welcome to the ultimate social network where plumbing gets the most attention and off topic non building is the second most important thing we chew the fat over. Although having said that there isn't much about building that is not covered here one way or another. Two three simple rules: To get an answer you have to ask a question - so keep it tight if you really want an answer as floating idea can cause responses to spiral all over the place The mind is like a parachute it is only useful when its open - so be prepared for the answers to be somewhat out of the box! You don't have to be mad to self build but it helps - the journey is hard, sometimes frustrating, always feels expensive and mostly very rewarding. Good luck

How the hell did you get the leader of the free, not so free anymore, world to do your tarot reading! I know he does it for a great chunk of the global population but your own personal prediction of the future? I heard the prog too as I was driving down this morning after an investment meeting with a business I am helping - v amusing.

Great to see a MAP, knew our LA (Canterbury) is not charging CiL and does not appear to have even started to think about it, but this is great reference for others given the strict sequence for avoidance. Speed reading, and good old CTR+F, seems to tell me that they are looking to reduce the number and range of exemptions, of which self building is currently one, but those that remain, which could be the self build exemption, should have a much simpler process so that bureaucratic errors do not punish. From which I take them to mean that if self build is to remain an exemption, which they don't say - and they don't give any list of exemptions that should remain, then it should be automatic rather than bureaucratic. SO it may or may not be good news, opportunity to lobby our MPs?

Thanks Jeremy. That looks like feasible document for me to produce.

Thanks again, mid supper prep, I guess I want to show the BR people that I have thought things through and in the end if I get the full 4 ACH in boot mode, for the internal WC/ en-suite on about the 75% speed setting and under 2 SFP I will be happy. Good point on the location of the inlet / outlet of the unit. My plan was run then straight up, cowell them both and have the outlet above the inlet by a meter or two. I am not sure I can get them separated much in X or Y given restrictions of the plot boundary.

Cripes Jeremy I only just posted this and an amazing response. I had read your stuff on ebuild many moons ago and was looking for SFP curves for your Genvex unit just now. It seems that SFP is one of the keys to quiet but I cannot calculate / estimate how much although I understand why it's important. Skuttlebut says below 2 is ok but below one would be better. I will digest your response , cooking supper right now, and tweak my plans.

The architect has now worked out most of the MVHR duct routes around our design and so we have to decide which ducting method to use. We could use the Metal ducting for the spine runs but then we have to go radial from the spine ends, and in one case middle. Having have a variety of discussions and looking at it I am unsure about which radial duct system to use. I guess it comes down to semi rigid (as Renson for instance) or perhaps the fully flexible stuff (such as BPC). There is also the choice of plenum / diffuser to ensure we have access, adjustment, match the duct cross sectional areas and meet the aesthetic requirements. There are several assumptions and issues that I can see with this choice: Assumption: that the supply and extract run together so the extract removes the same volume of air as the supply provides (appreciate there will be some small gains / losses) so no positive/negative pressure situation. Assumption: part F purge rule applies to the internal 'wet rooms' (IE no windows) and we have extended this so that we can purge all the wet areas according to part F all calculations here are based on boost mode to part F (2010). Assumption: that we provide relatively open routes between supply and extract, door gaps for instance - so noise is limited and differential pressure is minimised (assumed zero plenum to plenum for calcs). Assumption: If the MVHR units extract line were perfectly (as in perfect collision) connected to the supply line there would be no back pressure. (IE internal resistance is zero) Assumption: Vent Axia say a well designed system, for a four bedroomed house will have a back pressure of 160 pascals so assume 180 pascals for our system as perfect we are not. Main Issue: Noise, we want to minimise noise from the system so the air velocity wants to be as low as possible for the required flow rate. Our volumes are not huge even in purge mode I am modelling on 75 l/s in boost mode (270m3 / hr.) and we are working on a 400m3 / hr unit so in boost mode running at about 75% capacity - without back pressure adjustment see below. Worst case (model) is 2.11 m/s air velocity in extract pipe (assume equivalent of 100mm internal dia duct) from the main bathroom. Issue: Simplicity of install, we want a simple install that we can clean out, as and when (hamsters etc),and that can get into small spaces so we can run up it stud walls etc (hence Renson or BPC type ducting) Issue: should I include a calculation that uses the diameter, surface area, and perhaps roughness of the internal surface to give me some approximation of the back pressure I will get from a length of the relevant duct and thus the increased noise, as a result of more work, from the fan in the MVHR unit as most of them provide a performance curve against back pressure. Rather than assume the vent axia value? Issue: Cost benefit - I guess I can decide on that! I guess what I want to understand / be clear about - and having made a few whistles in the past, albeit steam, is what the effects of the duct choice will be on the noise and how the plenum / diffuser combinations 'tune up' against the two duct types. Ventilation calcs Part F.pdf

Ian, just working our MVHR design and wondering if you have closed this one out yet?

You need to make a frame to hold the L bars in place ready for the pour and pour around them. You should not insert them after the pour because: a. You won't be able to get them placed accurately - if you push them into very loose concrete they will probably move either sink or fall over. B. 400 will take time and even if you get the first into the concrete by the last it will have gone off. C. You need to vibrate / poker the concrete to ensure it flows around the bars which are profiled to ensure they are held firm and you cannot vibrate concrete that has started to harden. Sadly a frame is required.

Key things on the plans are any relative dimensions to adjacent buidlings or heights that are critical. On our planning we needed to show that the ridge was on a line between the two adjacent ridges and that the new gutter level was only 400mm above that of the old building. Also because we could have had a right to light issue we included a sun track / shadow section to show that the new design did not overshadow and we provided the functions of the rooms in our neighbours house for windows we might have ended up overshadowing.

You might be able to raise the floor but there are things to consider. First the ceiling height will reduce and you may hit building control issues. Second the heights of everything else will need adjusting, doors. Windows, plug sockets, light switches etc. Finally any related inside and outside levels will need to be reconciled - steps etc.

I am going over to Maidstone at the weekend to 'build it live' to close the deal on our windows and happy to say hi to any others here who are going down, PM me if up for a face to face, coffee, beer, sandwich.

I am sure that many will realise that self building is not for them - self building is not for the feint hearted - well you don't see them on here do you, but some will be prompted to give it a look and then give it a go. Like most of us here we are not trying to make a profit, we have targetted our build cost, everything, at the average selling price for similar sized houses in the location we are building. Although the other half got a shock the other day when she spotted that the house opposite, slightly smaller than our build, is up for £100K above the average selling price. We have a 10 year view and have worked out energy, servicing and house price fluctuations in our model which helps us be confident that we will both have the home we want at a cost we can afford in the medium term - our offspring will get the benefit if there is any. We are targetting £1200 m2 and the budget is running out just below this on the progress / spend line, we are doing as much of the work as we can ourselves to manage cost and ensure quality. Budget is everything as you might expect and if you are not up for some of the heavy lifting (not literally) you can expect to pay top dollar. @JSHarrisI think there are many ways to skin a cat in terms of how you apportion that budget. We are, in effect stick building, so have an on board SE - but I guess / cannot recall from your blog, you had your SE work done as part of the timber frame package. We don't have the aesthetic skills to think through a properly proportioned building within the envelope we have so chose to use an architect (the full RIBA package as far as detailed drawings). We will always live in a one off architect designed home and that does have a market value albeit indeterminate, I am not sure we have direct value for money but the 10% (Architect and SE) of the cash budget is going to be about it on our build. So we have those two but won't need spend in other places, we have no difficult ground (yet), we have mains water, sewage, gas and a PME mains supply (could have three phase if we wanted as its on the pole that is on our land) so we saved there. I have costed my time into the budget using a mixed mode formula - I could be earning elsewhere if I wished to but luckily don't need to, so it is part of the build cost. I did wok out a formula to cost each of the trades against my time and my estimated efficiency against a full time pro but it got silly / complicated so I abandoned it and just put in a figure based on a simple analysis of the housebuilders bible.

Tend to agree Jeremy but there may, just may, be a campaigning angle to this series, unlike GD, where Charlie, or the producers, actually think that they can support the self build movement while making entertaining TV. As I think I have said elsewhere most, if not all, such programmes have a nugget or two of interest for the observant viewer - and this week for me it was the house they visited in Glasgow and the glazing in the main featured house. You do have to learn to see past the hype and make a realistic assessment of the cost / value see-saw.

Many thanks Peter that looks great let's see what the other half thinks.

Interesting point! I to have buried traps in our design and the traps are rubber olive and nut joints. I wasn't worried about the joints as we have exactly the same set up here in our ground floor wet room and it went in 12 years back and so far no problems.

I haven't got Rationel windows, did you mean Rehau? Sorry Peter, my mistake. A pic of the corner without mitre is all I am looking for I guess if Rehau can do it they all can.

Hmm specification seems rather vague. Does he want a love seat - sitting offset side by side looking in opposite directions - its all about eye contact, a seat he can love, a seat he can make love on / around / over or none of the above or all of the above.