BadgerBodger

I’m reading your other thread and thought I’d throw my two cents in… Perhaps I’m a little more prone to taking risks but if the overall upstand size still fits (I.e the rooflight can still be installed over it), the upstand is at least 150mm on all sides from top of the flat area of zinc and the workmanship of the weld detailing is acceptable (you’d have to make the call on that or get a consultant to comment) and velux haven’t explicitly stated that it can’t be installed over multiple layers of zinc, I’d be inclined to install anyway… If you are still unhappy, the zinc layering means the rooflight doesn’t fit or the upstand is too short, have you considered extending the upstand with solid timber and/or cutting back the zinc in the bracketed areas using a colour match GRP to dress in the detailing. Yes it might not quite give the aesthetic you want but many GRP specialists warrant their work for 20+ years. In industrial roofing with Kalzip (a similar albeit not the same product) this is a typical detailing solution for unplanned or overlooked penetrations. I’m sure if you spoke with the roofing manufacturer and velux technical teams a simple enough solution is in front of you. As much as we would all like it to be, building on site is not always a precise science and one has to be dynamic and pragmatic about things like residual risk in situations such as this. The main problem is that for the most part, most people only think about THEIR job and not how it interlinks, impacts or even obstructs a subsequent task. In fairness I am often frustrated by this but I have to remind myself that it is not their role. Adding to this frustration, the architect does not include explicit instruction and provides “typical” details which overlook the most complicated scenarios (in your case, where the materials overlap). There are many reasons for this which often includes an inability to half the issue in their minds eye and permissible dimensional and installation tolerance in accordance with the British Standards. Adding to this confusion are the manufacturers guidance notes which in many cases are only available by request and are more restrictive than the British Standards which architects specify to. As others have said, don’t beat yourself up about this, it’s a typical conundrum, but it’s also a situation which would be “overcome” by a site or project manager by opening dialogue with all the relevant parties albeit sometimes circumventing a difficult contractor and just telling them what the solution was.

Glysophate sounds like the solution here. Maintain that scorched earth look like a champ.

For building regs you normally need ties 225mm from wall opening jambs at 450mm vertical centres (I think). More than likely an issue…

I found that once I got most of the bigger players discussed here down to the same spec and scope there were much of a muchness for the material cost +\- 10% or so. It was the fitting that varied the most and I just want entirely sure with some that I wouldn’t get more costs down the line. In some cases fitting wasn’t offered. Installation, surveying and delivery varied the most being between 40 and 60% of the material cost. We went to VELFAC, Nordan, Norrsken, Rational, internorm & 21 degrees. Or relevant rep installers. Some were just plain difficult to deal with and went off the list. We’ve needed up with Norrsken based upon reading here and elsewhere. Would have like Nordan (used before) but they didn’t offer fitting. Being honest the Norrsken windows are the only ones we haven’t seen but in reality IMHO they were very similar with the main leading difference being the larger the frame size, the more “solid” they felt. I wasn’t so keen on the Belgae ironmongery (too spindly) and it was the flimsier feeling of them all. The only exception being the internorm lift and slide which was truly magnificent!

I think this is the detail you are looking for…

Yes, it’s the upper floor UFH i am most concerned about as opposed to the flow/return to the manifolds. I know everyone says that UFH likely isn’t needed upstairs but because of the high ceilings and general area I’d rather have it and not use it that not have it and want for it! So here if the surface temp of the floor was say 30 degrees and the RH within the house was 50% the dew point would be around 18.5 degrees meaning the flow temp of the water in the upper floor area would need to be above that because the UFH pipework isn’t insulated. Or am I missing something?

My worry is in the upper floors where pipework runs in a joisted floor. I’m not sure what the air temp might reach because of the larger space, air tightness and increased insulation but unless I’ve misunderstood, the table below indicates that my current room in roof dew point in summer at 40 % rh and reaches 35 degrees quite regularly, the dew point is just above 19 degrees. How would I manage the flow temp to ensure it runs above the dew point for the relative RH? I could probably tolerate a wet floor in the tiled hall. I wouldn’t want soggy ground floor ceilings.

Shoot me down. This works in my head… Back at university when completing a mechanical design module I recall designing an energy efficient solution for cooling using passive chilled beams. As a concept does using a couple of chilled beams in a central hallway for cooling at high level (8m above ground floor level) with an ASHP and MVHR to encourage circulation of that cool air and subsequent recovery/recirculation… To reduce the weight applied to the roof structure I’m looking at using PIR to ensure a low u-value but I’m worried about overheating in the upper floor area (which resides in the roof space). They are large areas with high ceilings (3.5m to the apex) and have limited windows apart from the hallway which I’m unsure if the will have a positive or negative impact. In my minds eye the chilled beam is a novel solution to reduce the risk of running the UFH using cold water and the associated condensation risks.

Have you tried keylite? They’ve come up way cheaper for me.

The advertised rate and the actual negotiated rates being so wildly different. Why not just give me your best price? I’m constantly surprised as to who is offering the best price, recently been to two specialist BM for roofing materials. Both were beaten by my local BM for a not insignificant roof area of 282m2. Timber, felt, lathe, trim, nails, tiles, the full kaboodl!!! Same goes for lintels. Why advertise a rate of X when the merchant will immediately give you 40+% off!

Groundwater comes up/across, surface water comes down. Rainwater would generally be surface water until it meets the water table. Most French drains are dealing with surface water only. Land drains can be dealing with either or both. Land drains tend to be used to manage the water table (in drained land) or alleviate pressure (behind retaining walls). There are variations on the theme .

Apologies, you’re right. That one is for the surface water. I did not need that test in the end as we are using an existing pond which has been used for the same purpose for the last 30 years. I used a generic test from one of the tank suppliers. https://www.jdpipes.co.uk/knowledge/sewage-treatment/how-to-perform-a-percolation-test.html#:~:text=The procedure measures how long,will come from the drainage And you are right. I did it wrong. I should have measured the time from 225mm down to 75mm but with the weather and me being in a general rush to get done (doing 3 tests at once) I forgot that and explained it to the BCO at the time. People make mistakes. In reality, my point was faster speeds can be accepted and that you don’t have to do it on three consecutive days. Which so far as I can still tell, you don’t.

Tough call. Are you draining groundwater or managing surface water? As a general rule I’d say textile all the way. In some exceptional circumstances I’ve seen them block (using non-woven). But these were truly exceptional.

Three consecutive days? I know the first “fill” should be on day one and the other tests follow but I actually thought you were meant to test consecutively on the same day so you get a cumulative impact (making the test take longer each time) which results in a larger drainage field. This is more important with poor draining land but not to be ignored. Either way. I did my own test as above, and got pretty low values (as in fast draining) but they were accepted (using PSTP). Admittedly I didn’t follow the guidance entirely as it was the middle of storm darragh… but I think it helped my cause. I also did three trial holes and tests picking the worst two for my final result. I used this website for guidance… https://www.copeland.gov.uk/sites/default/files/attachments/percolation_surface.pdf

No!!! The total build-up was 1.4m. If I recall it was geotextile, geogrid (Tri-axial) 300mm 75-125 stone, three times, with 300mm 6f2 and an MOT capping to make-up. It was a for a pile mat. The permanent structure was built on driven piles. I don’t think It’s absolutely necessary. I was looking to use grid at my place but given that the drive is caked in mud at potato harvest I figured grid wasn’t any use as it would be gunked up with much after the first winter.

@Redoctober I use the membrane below the type 1. It’s mainly out of habit now as every road, car park, plaza I do seems to have it so when I’m doing myself I figure I never have to go back to that spec so if it’s good for them, it’s good for me. Anecdotally, in my experience it helps with ensuring you don’t get such a migration on fines (upward) from formation level. Over simplifying it, geogrid type product greater resist punching down. I’ve had some pretty bad ground in my time and pretty much every time a combination of geogrid, membrane and stone in varying thicknesses generally gets the result we need. In some cases for pile mats I’ve put in 1400mm stone!! The rest of the site received cement stabilisation.

Angular gravel is the way. Essentially quarried only. As everyone else says river bed gravel, shingle, pea gravel or otherwise, spills, ruts etc. Up to 50mm of angular gravel on a good sub base (minimum 150mm MOT) with woven geotextile below is reasonable (substrate dependent) for passenger vehicle. The MOT wants compacting well (twin drum roller ideally) and the gravel should knit well. I recently did a temp car park on bad ground and we swapped out the gravel for 150mm of 40mm clean compacted and it’s held out for 3 years of heavy use.

Yeah, this client is not domestic but energy infrastructure. It’s not a case of want, more need. And the need is ours and their desire to make money.

@JohnMo I’m not sure you’re entirely correct on this point. The uk manufacturing process has been improved across the board and the average improvement is a 29% reduction in embodied carbon as an average in the placed product UK wide. You’re right, not everyone uses the best, lowest carbon products, but some do, the project I am on now has used 3500m3+ of concrete. Wherever possible we have used GBBA cement replacement at the maximum potential (it’s actually cheaper and your concrete supplier will give you a mix design with this in as standard unless you ask for 100% OPC which most people don’t actually want because is has a short workability period and unless places and protected properly is prone to cracking) . Wherever possible we also used recycled aggregate and placed 16000m3 of crushed concrete in lieu of virgin crushed rocks. And this is not a government contract. This in part because many institutional clients WANT do to the right thing. They sign up to optional scheme like BREEAM which push sustainability above and beyond the mandated standards. It’s much akin to the much maligned Euro Rules many justified brexit on, not realising we as a country went above and beyond, often by choice. You might not realise it but it’s happening right in front of our eyes. Because… the system of taxation… incentivisation… works! Another example of this is EV. Uptake wouldn’t be so high if the sales hadn’t been subsidised in the way they were. And subsequently if infrastructure requirements hadn’t been pushed through the various routes (subsidisation, investment, planning etc) but for the most part I think we can again agree that the trajectory is by and large “in the right direction”. And yes, big compromises will be made to “finish the job” but as ever you have to consider the pareto principle (80/20) rule. The premise of which is that inferred in this situation 80% of the gains will come from 20% of the effort. I think we’re still that 20% phase and importantly this trajectory is a 25 year plan and by that standard, the next 5 years will see the most gains with the least sacrifice. What happens next is anyone’s guess…

I’m not sure I’ve ever seen oak oudoors, not silver unless regularly treated. Lame goes for larch. And bothe look pretty similar in the end. As a soffit it might well be that as it’s not exposed to uv or weather, it may last a good while. I fitted this (not in wood finish) and the colour 5 years later is still good a strong when exposed to full daylight on a facade… pretty much 0 maintenance. https://www.trespa.com/en_GB/products/wood-decors

Have you looked at a shallow crate system which could then have a hydrobrake on the exiting MH?

Agreed. Compromises will be required. But incremental improvements combined with small changes in lifestyle/approach can make a huge difference. Sometimes there is very little compromise for the end user though, just look at concrete, still a major source of carbon emissions the production of cement has been improved so as to reduce carbon emissions by roughly 50% and development in concrete design by use of cement replacements such as GGBS mean that overall embodied carbon is reduced by nearly 30%. This is an averaged number and can be further reduced by use of recycled aggregates and increased GGBS in some applications. Proof that legislation, taxation and incentivisation works. This kind of approach cascades into developing worlds (eventually) through the realisation that it can and does save money in the long term.

This. Leading by example is the only way. If everyone takes the approach that “it’s not my problem”, no-one does anything. Everyone does their own bit. Like you say, the “20 billion” is small fry, and I don’t know the exact numbers but some if not all will be covered by the various “carbon” taxes.

Yes. They do. But most don’t have off street parking which, unless you are willing to put up with the inconvenience of have to go and sit somewhere to charge or they have charging everywhere you park (work, shop, etc) an EV is no good. Where I currently live it’s virtually all terraced housing (Leeds) in the main city…

Interesting topic. My two cents for what they’re worth. like others have said EV works for city dwellers. But not for most as they’re both too expensive AND impractical for anyone without a private driveway (currently, but likely not forever). EV models are marketed at that size and affordability range upwards. side note… as much a I hate all these e-bike everywhere they do seem to potentially be a part of the solution ICE for me is providing best value for money based on a 5 year usage cycle when considering purchase price, maintenance cost, fuel and resale value (so long as I only buy - nearly new). That IS changing and the tipping point is getting closer to viability on a cost basis BUT as a family we would not be able to have two given the current mileages capacity. I see electric cars as the Betamax. Something else will likely be VHS maybe a hydrogen fuel solution or maybe something we simply haven’t thought about/isn’t yet practical. re carbon capture. I have mixed feelings about this. I’m a strong believer in forward motion and this is an important step for lack of a better solution. The concept of carbon credits is forcing companies to start thinking about their own solutions (to carbon emissions) which should stimulate creativity. In this case maybe we need to rethink the problem as having another dynamic - tax. If you consider the impact of the laffer curve on business in combination of incentive effects the policy make more sense, hopefully stimulating yet more innovation and development I think carbon capture is a step in the right direction and the development of efficiencies in the technology is right BUT that solution for sequestration could be a misstep, or at least, only a small part in the long term solution (which in all likelihood will land on - plant more forests!!! - a topic for another time perhaps…) coming back to carbon capture, it’s not all about sequestration but some is actually re-used for manufacturing amongst other things. The reality is we, have to think more about what we are doing with our waste, because in my view, that’s what this is, a waste problem, which is solved by a multitude of factors but started by attacking the biggest generators which are energy production (in its various forms and usages), and quite literal waste. As usual the hierarchy of control should be eliminate, reduce, re-use, recycle, dispose (responsibly). EV is quite high in the hierarchy with it reducing emissions carbon capture sits lower on on the re-use/recycle/dispose levels but when you consider that with current processes carbon must be generated, carbon capture is the next most responsible thing to do. ultimately both are steps forward and forward motion is forward motion which is better than stasis or regression.