Jeremy Harris

I'm guessing that this is the Part L1a figure, which is m3/m2 internal surface area/hour at 50 Pa pressure differential, rather than the far more sensible air changes per hour figure that everyone else in the world seem to use................

In the light of experience, I'd say that floor sensors are a "nice to have" rather than in any way important. Mine's only used for data logging now, and frankly I don't bother looking at the floor temperature at all most of the time. All that's really needed is a way to be able to run the UFH pump when the heating/cooling system isn't running, to allow the redistribution of heat around the slab a bit faster than just letting it stabilise over a longer time period. This depends very much on how much solar gain the sunny parts of the slab get. Ours used to get a lot, but once we fitted the solar reflective film on the outside of the glazed gable that dropped a great deal, so there is far less of a requirement to redistribute heat around than there used to be.

Welcome, sorry I didn't recognise your user name here! No need for any experts, all you really need is an idea as to how well the sub-soil drains, and it's a pretty easy DIY test. The standard test is called a percolation test, and is done in accordance with the procedure on page 32 of Part H2 of the Building Regs: https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/442889/BR_PDF_AD_H_2015.pdf Here's the quote from the relevant section, to save having to look it up (ignore the bit about the Environment Agency - it's not normally applicable to rain water run off, and don't take too much notice of the bit in section 1.33, as it's mainly aimed at sewage treatment plant drains): Also, don't take too much heed of the suggestion that the test should be carried out three times. In my experience, BCOs only usually bother to check once, if that. Depending on the Vp, you can then start designing a scheme to comply with SuDS, and it shouldn't need any experts - if in doubt we can help on here with ideas.

Our 1 1/2 storey house has the same, a large ridge beam with the deep rafters hung from it. There are some photos here of the frame: http://www.mayfly.eu/2013/10/part-eighteen-a-house-in-4-12-days/

If I laid a drive like that here it would never drain, and would just flood the lane, I'm afraid. Compliance with the Sustainable Urban Drainage requirements depends very much on your sub-soil, specifically on how permeable it is. The best bet is to do a quick test to check this (easy, dig a hole, pour water in, time how long it takes to drain away - there is a standard procedure) and then work from there. Once you know how permeable the underlying sub-soil is you can look at the options you have. We're close to being a worst case, and I ended up having to fit 20 off, 196 litre, heavy duty Aquacell drainage crates, wrapped in terram, in a large excavation below our drive sub-base in order to act as surge storage, to prevent water from heavy rainfall washing out into the lane.

The Ultranetworks system is similar to the wireless system that Paul Camelli (the blog link posted by @Triassic) has, I believe. Speeds are good and latency is much lower than a satellite link, as the signal isn't having to do a 44,500 mile trip (that alone adds around 300ms each way, so around 600ms latency). The satellite latency has to then be added to the normal network latency of around 20 to 40ms. From what I've read, local wireless link systems like Ultranetworks, have a latency that's no worse than a fibre broadband connection, and has speeds that are better than standard ADSL.

Depends how deep the invert level is. The deeper the invert the harder it is to rod from a small chamber. You can get very flexible roll-up type "rods" that will bend around enough to get in through a small opening, but the only time I used one I found that I couldn't push hard enough on it to clear the blockage, and ended up getting DynoRod in (a whole other story - suffice to say they were a shambles..........).

Pity you didn't get it on video, could have been used as advertising by the people that make the stuff (think along the lines of the puppies and toilet roll............) On a serious note, nothing bonds to polythene, it has an extremely low surface energy, so to get any adhesive to bond to it long term requires something like plasma treatment of the surface to increase the surface energy. Having said that, there are some adhesive tapes that bond reasonably well to the stuff. Polytunnel repair tape works well, and although the bond will degrade over a few years, that doesn't really matter much for a warning tape.

Definitely take heed of the "only superglue the joint covers on one side" tip and very definitely leave an expansion gap, as uPVC expands like crazy when it gets warm, and black uPVC will get very warm in sunshine. Our fascias are fine, as the roofers fitted them properly, but around a part of the uPVC fascia that I used at the base of our larch cladding we have one split joint plus a big bow in one section, where the expansion forced it off the underlying battens. The guys that fitted it didn't leave either a big enough expansion gap or only glue the trim on one side.............

Cousin Jack

Further to the above, I've been digging out prices if anyone wants to mix their own pump corrosion inhibitor. It seems that the Graco Pump Armour is a bit pricey, at around £16 per litre, so it's worth looking at a cheaper option. For those that want to make their own "pump armour", then here's a recipe, using stuff from ebay. Bear in mind that this will produce the same concentrate as the Graco product, so needs to be diluted in the same way before use. This is actually a 60% ethylene glycol, ~1% sodium nitrite corrosion inhibitor mix, so near-identical to pump armour, and at least well within their production tolerance, right at the upper end, so it will, if anything, be slightly more effective. Buy 5 litres of 100% ethylene glycol (around £20 from ebay) and 250g of sodium nitrite (also from ebay) for around £5 (this is more sodium nitrite than needed, but it's cheaper to buy 250g). Mix 50g of sodium nitrite to the 5 litres of ethylene glycol and then add 3.3 litres of water and stir well. You now have 8.3 litres of "pump armour" concentrate, for the princely sum of about £25 (with enough sodium nitrite left over for four more batches). Dilute and use in the same way as pump armour. The only differences between pump armour and the above mixture is that pump armour costs over five times more, and this home made version doesn't have the blue dye and bittering agent that's added to stop people drinking the stuff. Chemically it will do the same thing, and provide the same, or better, level of corrosion protection. If you don't want to bother making the stuff, then buy blue antifreeze concentrate (not the red or purple stuff) and use that. Any decent brand of blue antifreeze concentrate will be around 40% to 50% ethylene glycol, and will have sodium nitrite as the corrosion inhibitor. The red or purple antifreeze is not ethylene glycol, and may contain silicates and be based on OATs, so is not suitable for this purpose. Decent quality blue antifreeze is about half the price of pump armour, so still a significant saving.

+1 to @Ferdinand. The dxf files are invaluable, as they should use the layered OS base dxf, with the topo and boundary features from the survey over-laid as additional layers. I used mine as the master template for every site drawing, as it was a true record of the actual site on the ground, not the inaccurate representation on either the OS base map or, even worse, the very inaccurate Land Registry Title plan. Being able to very accurately tie everything on site to a common base survey was extremely useful - I could plan drain runs, the layout of the drive and landscaping, take accurate measurements of volumes of stuff to be removed etc, all from one set of data.

OK, just checked the chemical composition of Graco Pump Armour, and it's 40% to 60% ethylene glycol antifreeze solution, with a tiny amount (0.1% to 1%) sodium nitrite as a corrosion inhibitor. This is identical to BLUE antifreeze concentrate used in automotive applications, sold as concentrate with between 40% and 60% ethylene glycol. Often the number in the name of concentrated ethylene glycol antifreeze is the percentage of ethylene glycol used. AFAICS, all BLUE antifreeze uses a similar formula - concentrated ethylene glycol plus sodium nitrite as a corrosion inhibitor.

So, "pump armour" is the preservative/anti-corrosion stuff that's in the pump when new, is it? The instructions for mine just say that the pump is supplied with a "mineral spirit preservative" that has to be flushed out well before first use, but there's no mention of using this for long term storage. As above, I had thought of doing this, using a home made mixture, but I'll go and investigate what this "pump armour" stuff is. If it turns out to be what I think it is, then I'll probably just make my own.

I seem to remember that mine was wet inside when I received it. I suspect it may well just be left over from leak testing during manufacture. I didn't have any problems with the Wunda manifold, other than finding that it is fairly critical to make sure the joints at the ends aren't under any strain. If the pipes connecting to the manifold put the end joints under any appreciable side load (because of misalignment) then those joints with the O rings can weep a bit.

Sorry, missed this earlier. I'm not sure exactly what you mean by "pump armour". My unit is pretty basic, just a motor driven high pressure pump, a high pressure hose and a pretty simple spray gun. Storing the unit after use is really just a matter of cleaning it out very thoroughly, and making sure it's well lubricated (mine came with a bottle of lubricant). When new, they are supplied with the pump unit partially filled with some sort of preservative, that smelt very like white spirit to me. There's nothing in the instructions for mine about adding something like this for long term storage, though. Having said that, it would be pretty easy to partially dismantle the pump and make sure it was clean and dry inside, and maybe fill it with something like a dilute oil/white spirit mixture, just to make sure nothing corrodes whilst it's in storage.

The best thing I have done recently is to fit one of these: http://www.ebay.co.uk/itm/Scaffold-Winch-Electric-Workshop-Garage-Gantry-Hoist-Lifting-125-1000KG-/272134167630?var=&hash=item3f5c75dc4e:m:mefkdAf5bNIRBz5lPNMMv1A (the £50 one that lifts 125kg/250kg) above the loft hatch in my workshop. I made up a "lift" platform from 18mm ply, some eye bolts and chain, and it's brilliant for getting stuff up into the loft storage space. This week I was finishing off the loft hatch and ladder fixings, and instead of using the rather cumbersome pole and twist latch for the loft hatch, I just fitted an eye bolt to the hatch, a couple of big tension springs and a shackle fixed to the springs to fit to the hoist hook. Having extended and rewired the hoist controls, so they now run through the ceiling, I can just press a button and the loft hatch and ladder either lowers or raises, with the springs holding the loft hatch closed.

I found that, when working on my own, it was always getting awkward stuff up, like ladders. Having the ability to just let go of the rope and have it still held securely, whilst I walked around to move something to stop it snagging was great.

The secret is to make the small triangular cut that's shown on figure 4 of these instructions (this bit applies to all the slate dry verge systems): http://www.kytun.com/v4/501b5369-a8d0-477f-97cd-4a81668870fc/uploads/Kytun - Dry Verge Fixing.pdf As the instructions say, highlighted in red:

There is a neat way to join it. There are instructions on how to trim the joins so that they fit together neatly with a clean overlap. I will admit that I had to show our roofers how to do this, and I also had to lend them my left and right hand aviation snips (without those you will struggle to cut the alloy neatly), but once I'd shown them how to do one join they did all the remaining joins quickly and neatly. The secret is to cut the material exactly as shown on the instructions, using very sharp, handed, snips, so there is no distortion at the cuts.

My experience is that COP barely changes at all with outside air temperature, but it does change LOT with outdoor humidity. When the ASHP is asked to deliver a high flow temperature on a cool and damp day then the COP plummets, way below 2, primarily because of the impact of defrosting, which can reduce the time that the ASHP is producing useful heat when running by around 20% to 30% on a particularly bad day, say one where the temperature is down around 5 deg C and it's raining or misty.. The difference in the heat available in dry air at 15 deg C and dry air at 0 deg C is only a bit over 5%, hence the relatively small impact that outside temperature has.

The crude app that came with my cameras will talk directly to the cameras in P2P mode, without them being connected to the LAN or WAN/internet, so it must just accept the stream and check it to the GPU for display.

There's more BS associated with cable and connectors for "Hi Fi" than you can wave a big stick at. I've heard some truly ludicrous BS before now, including claims that "skin effect" comes into play at audio frequencies (it doesn't at all) and a host of other garbage. Around 30 years ago, when I still had access to a decent lab at work, I did loads of measurements on different cable and connectors, using a (for the time) state of the art Hewlett Packard network analyser. Not once was I able to measure any difference between the "best" cable on the market and a cheaper bit of ordinary copper cable of the same CSA. That didn't stop a fellow Hi Fi nut friend claim that using gold phono plugs improved the sound of his system (even though gold is not a particularly good electrical conductor, it's 30% worse than copper............).

Me too, I think it's probably the cheapest form of reasonably thick section copper you can buy, and fine for fixed speakers set in walls or ceilings. You're unlikely to be putting lots of power through wall/ceiling speakers, anyway, and I doubt that anyone would be able to hear a difference between the very best oxygen-free copper speaker wire and a bit of 1mm² or 1.5mm² T&E.

What I did was pre-empt the valuation office survey, by sending them a detailed floor plan with dimensions and floor areas marked, accompanied by a letter explaining that the walls were much thicker than normal. No one came to look at the house at all, they just did the valuation based on the information I gave them, plus some comparisons with the sale prices of nearby houses over the past few years.