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Having originally planned then dropped the idea of Solar PV (a combination of budget constraints and drop in FiT rates) I recently acquired a number of Solar PV panels (a pallet bought in conjunction with @ProDave from Bimble Solar via Ebay). Having recently collected the panels, lengths of mounting rail and various other bits and bobs @ProDave had kindly sourced, I fitted the system over the last two Saturdays. First off was mounting the rails on my rear, SW facing garage wall. I decided to mount the panels vertically simply for ease - a ready made structure to fix the rails to, and easy access to a consumer unit for the grid connection. There is a penalty in terms of a reduction in annual generation compared to a sloped array, however simplicity won out. The following picture shows the garage wall with rails fixed; To start I nailed packers to the cladding to ensure I had a drainage gap behind the rails. I then fixed the rails (Unistrut - a tip from @Onoff) through the cladding, cladding battens into the timber frame of the garage using timber drive bolts I happened to have. As the lengths of Unistrut I had were offcuts (only way I could transport them) I used joiners secured to the channel with bolts/channel nuts. Finally, I added hanging brackets for each panels to help carry the weight of each panel / so I wasn't reliant purely on bolts clamping the panels in position. I fitted the panels, sitting them on the hanging bracket and bolting them around 300mm from top and bottom as pictured; The ends were secured using Z brackets I cut down using a grinder (thanks @JSHarris) so that they clamped only the frame and did not overhang the panel itself; Long M6 bolts with large washers were used to secure the panels into the rails where they met with each other; The channel nuts (also known as Zebedees) into which the long M6 bolts were secured; I used M8 bolts and channel nuts for the joiners, end and hanging brackets. My electrician connected the system up, wiring the panels to a DC isolator, into the Inverter which in turn is wired into the garage CU via a meter and AC isolator. 2 hours work for him. Switched on, the Inverter ran through all its self tests and everything okay. Sadly at that point it clouded over and the heavens opened so only a few watts being generated. Fortunately, today has been a bright and sunny day (albeit a bit hazy) and my 1.5 kWp system is as we speak, generating 1.2kW. The following shot was taken yesterday just before the rain came on, but all in all, I'm pleased with the way it looks (panels mounted so they read visually with house windows). Cost wise the system (1.5kWp plus a spare panel), mounting rails, nuts, bolts, brackets, isolators, meter and electrician (@Prodave was kind enough to give me the DC cable he had left over which was just enough for the job) total £550. I already had the inverter. Final job within the next 28 days is to notify the DNO of the installation.

How about buying a garden sail to shade the window this summer and see how this works without spending money or time designing something “proper”. You can even put it up and down a few times to help your decision making process. Modelling is all well and good but real life is sometimes different.

In Part 22, I detailed my decision making process in relation to my choice of a pre-plumb Mitsubishi Ecodan 8.5kW ASHP based DHW and heating system. I now have a full set of data covering 12 months so can provide figures in respect of how the system, and our house has performed. My baseline requirement was to maintain 21.5C in the house 24/7 throughout the heating season (October to April), and a supply of DHW water that would allow multiple showers to be drawn off without a drop in the temperature of water delivered at the tap. The Mitsubishi FTC5 master controller / thermostat is set to 21C, and is located in the hall next to the vestibule. DHW is set to and stored at 50C. Over the 12 months March 2017 – March 2018, heating COP ranged between a February low of 3.3 to an October high of 4.6 over the course of the heating season, with an overall SPF of 3.7 DHW COP ranged between a February low of 2 to a summer high of 2.5, with an overall SPF of 2.3 Based on a kWh electricity unit price (inc standing charge) of 12.3p, I paid 3.32p per kWh of delivered heat, and 5.34p per kWh of DHW (inc losses). It should be noted that DHW cylinder losses do slightly reduce my heating demand, albeit at a higher cost than if delivered via UFH. For a reminder of our layout: In winter, with a set temperature of 21C, the house sits at a comfortable even temperature, the main living section of the house tends to sit at 21.5C, the 2nd and 3rd bedrooms at 21C and the master bedroom at 20.5C. I suspect that the slightly lower temperature in our bedroom is due to the fact I set the MVHR vent at a higher supply rate than the other bedrooms. This would tally with my experience of doing the same in our last house. The two biggest factors that impact on our heating demand are wind speed and solar gain. In modelling our heating requirement, I took both into account, along with incidental and household gains. The weather data set was based on a combination of met office and local home weather station information. Our average wind speeds are significantly higher than elsewhere in the country, and combined with the effect of storm force wind speeds (which we get a fair bit of) we do have a higher heat demand when compared to the same house being located in a sheltered inland area. The impact of wind speed, and the differential in pressure it causes is illustrated here: http://www.wanz.co.nz/ConversionChart A doubling of wind speed sees the pressure increase by a factor of four. Average winter wind speeds of 15-20mph (which equates to the standard air pressure test) are common if not the norm here. Average storm wind speeds of 40-50mph gusting to 70-80mph are also common. The impact of the pressure differential that such wind speeds cause was illustrated to me during the build whilst I was decorating. Having masked off the windows with polythene it was noticeable that when wind speed exceeded 40mph, the polythene would inflate on the windward side of the house, and be sucked onto the glass on the leeward side. Whilst we’re not aware of any drafts and the house isn’t any way uncomfortable, looking at the daily heating requirement when wind speeds are high, you can see an increase in the amount of energy used. Part of that will be air leakage (as evidenced by the effect of pressure differential on the windows) part is the unbalancing of the MVHR (gusting wind from a particular direction can cause the fans to struggle), and part is the lack of solar gain on such stormy days. In terms of solar gain, the vast majority of any gain manifests in the public areas. In winter this provides a useful uplift in internal temperatures. Depending on how clear it is, and how long the sun is out, the uplift sometimes compares to having a WBS stove on and really is quite pleasant. More generally, with mixed winter weather, the gain is less noticeable in terms of a temperature spike, but does have the benefit of reducing our heating energy use. In summer, the gain can be significant and does require a cooling strategy. Without any active cooling, the house has at times risen to 25C in the public areas and 24C in the bedrooms. Alongside the MVHR summer bypass (set to activate when extract air is 22C or more) we cool the house down to a more comfortable 22C using cross ventilation, opening windows / taking account of the prevailing breeze. We also have a velux window upstairs, which when opened in combination with a downstairs window, creates a chimney effect that is very effective in exhausting hot air. The biggest downside in using cross ventilation is that it doesn’t work when the ambient temperature is high (not a very common), nor when there isn’t a breeze (again, not very common). You also have to factor in the unexpected as we had to recently as our neighbour undertook ground works, which created vast clouds of dust in the dry weather. Opening windows simply wasn’t possible on those days. Overall the predicted impact of solar gain is as I modelled it using data from the following two sites: https://www.susdesign.com/ http://re.jrc.ec.europa.eu/pvgis/apps4/pvest.php PVGIS provided daily average data, and from susdesign I was able to work out a peak solar gain multiplier to determine what the maximum likely amount of solar gain would be on a clear, cloudless day. Modelling solar gain for both heating and cooling requirement was a very worthwhile exercise as I was able to determine what our worst case requirements were for both, and what strategies would work. I’m fortunate in that the prevailing weather conditions here mean cross ventilation is a viable and workable strategy to deal with overheating. I am however in no doubt that had we built our house in a sheltered location in a warmer part of the country, that we would have a very real overheating problem and would have to use a very different strategy, most likely combining solar films on windows and active cooling. I do have the option of actively cooling my house using our ASHP, via the UFH and if I wanted by retrofitting a duct cooler into the MVHR system, although haven’t felt the need to do so yet. One plus point of the Mitsubishi Ecodan ASHP is that activating cooling is simple (changing a dip switch setting to enable the master controller). All in all, I’m very happy with the way the house is performing in terms of retaining heat and providing a comfortable environment in both winter and summer. The performance and running costs to date are certainly more than satisfactory. Of particular value to us is having sufficient heating capacity to deal with spikes in heating demand (resulting from especially stormy weather) as and when needed, without having to resort to auxiliary heaters or peak rate top up, and the simplicity of use of the master control system. Whilst I could if I so wished set flow temperatures and heating curves, the onboard auto / adaptive program requires one user input – internal set temperature, and the controller works out the lowest temperature way of delivering it. Whilst I had a very good idea of what our heating curve should look like, using the auto / adaptive mode saved a lot of trial and error, and having monitored flow temperatures, have not seen them exceed 32C. For those not comfortable with developing their own programming or control systems, this is a very big plus. Having looked at a variety of options, I concluded that an ASHP would be the most cost effective solution (even after taking into account the cost of replacing the outdoor unit after 10 years) to meeting our requirements, and 12 months on, I have absolutely no doubt that I selected the right system for our requirements. Whilst I have no hesitation in recommending the ASHP system I have, it is important to recognise that low energy or passive type builds really do need to be modelled and individual requirements identified to determine what type of heating, cooling and DHW provision is required.

I've been told I can't start making a brise soleil until the garden is finished. We won't need one by the time that's done.

Don't forget @Construction Channel on you tube

"Ooops" is very useful. But I once said "Ooops" when I had made a mistake in a team building exercise, and I got a distinct impression that it was insufficient self-abasement. Umpteen apologies and bootlickings were apparently expected, and I think they would have been happier if I had done a self-imposed Joan of Arc solution. Like a forerunner of modern politics. Crowd-sourced Welsh suggestions here. F

Certainly striking! Looking at the profile, I would assume it can contain a standard LED light strip. The strips come with a sticky backing. There are loads available on Amazon, and even "smart" ones from providers such as Philips Hue. Yes, a small controller would be needed but one controller can run multiple LED strips so you'd not necessarily need one per section. Strips can be connected together using various connectors which you can buy separately.

ps - that photo is NOT my ensuite! ? I wish!!

The local Screwfix had WiFi repeater socket outlets on display last week. https://www.screwfix.com/c/electrical-lighting/switches-sockets/cat830530?switchessocketsproducttype=wi_fi_extender_socket

For ceiling APs, such as the Unifi ones, you can paint them (with not metallic paint). The cover comes off easily. You can even buy sticker skins for them. Ubiquiti's getting in on the game too. The new Unfi Nano has skins available made by Ubiquiti.

The other thing you need to consider is the route the various service pipes will take, look out for structural elements that can’t be drilled or notched.

It's a good idea, but I am fairly certain no such thing exists. Proper WiFi access points need to be wired back to the main router using ethernet cables. If they are just wireless they slow down the network. Indeed your ceilings do end up with a lot of bits and pieces there but they don't seem too intrusive. I tried as much as possible to put things where they cannot be seen, for example we have chimney breasts where I put switches on the side you couldn't see when you come in the door. I put wifi access points in wardrobes in some rooms and behind TVs, but we ended up with a few on the ceiling too. If you really don't want to look at them though you can probably hide them all like this. Bedroom ones will work from inside wardrobes, or even above the ceiling plasterboard. They are thin enough to put behind TVs mounted on the wall also.

Not trying to spend your money but there are companies that do it. This one picked at random (Bolton): https://roofinvestigations.co.uk/dye-testing/

Our plant room is downstairs, it’s more like a plant cupboard in the cloakroom, with a washing machine etc (all the crap) and it’s right next to the ASHP on the outside so very short pipe runs. Glad we did it this way.

Speaking purely from personal experience, I really, really wish I'd designed our house so that the plant room was downstairs. Having heavy kit on the first floor is a PITA, that was rammed home further last year, when I swapped our old Sunamp PV (~70kg) for a new Sunamp UniQ 9 eHW (~160kg)...

I found running the pump fully modulated provides best COP - usually 30% of max capacity is the lowest speed. So running at max capacity to take advantage of the shorter hours for E7 will result in lower COP - both because it is colder at night and because you are running at full power. This may not matter as E7 is "half-price" - your bills should still be lower. I prefer to run it at a fixed set temperature 24x7, so I can get away with a smaller pump and run it at lower power / higher COP. Plus, I have PV so running in the daytime can give me free electricity on sunny days. I do not have E7, our consumption pattern (bearing in mind said PV) does not makes it worthwhile as daytime prices are higher. As a reference, I have 7kW ASHP with a 330m2 house built to PH standards. This provides both space and DHW.

I’m sure it does, total clusterfruck of a situation for you, sorry but it’s just gone beyond my pay grade...... hope someone has a good idea.

Don't do this, WAIT for someone more knowledgeable to comment... That inside concrete reveal under the roof lights, could you paint that with black concrete paint so you can see if water runs down it. Thinking bare concrete will soak anything up?

Ive got some...had extra put in after the hairdryer fire. Will see if I can find the brand.

I was sent on a course like that, on Dartmoor, with the raft having to cross the Dart to rescue a "casualty". In our case all the teams worked in parallel against the clock (and each other) to build the standard "four oil drums, two planks and a length of rope" raft. By pure luck, that summer I'd been part of a raft race team (the annual one organised by Truro Rugby Club back then). As a part of training for that race we'd worked out a very quick way to lay out the rope in a zig zag, place the drums and planks over the rope, then lace the whole lot together through the open ends of the loops, pulling the resultant lashing tight at the same time. Seeing that our challenge was pretty much identical, I quietly briefed our nominated team leader and he agreed that we'd use the same method. Not only did it work very well, but getting our raft into the water about 10 minutes ahead of everyone else caused a load of panic. One team tried to prematurely launch their raft only for it to fall apart as soon as it got in the water. One of their team members opted to remove his shirt and trousers and wade in in his underpants to rescue the debris, only to then discover that his Y fronts went see-through when wet. Everyone else said we'd cheated...

@recoveringacademic Excellent response ?. Especially as I am the one always asking for their objectives from newbies. The question was quite deliberately open, as I have not focused it yet. This question is a conversation ! More usefully, the immediate end-in-mind is To repurpose content I have created here and elsewhere on my own resource. That has lots of elements to it. Which leads to the first two of many questions, these thinking about the form of such a resource and the way to set it up wrt to technology and integration of online services: 1: What will, in 2020, a beneficial, conversation generating online resource look like? 2: How can the 2019 internet be best used to generate such conversations? And the question for this thread which is a starting point: Which examples of resources around self-build, construction, design use the contemporary internet effectively? How do they do this If you want to move this thread to the members only forum, that is fine. Ferdinand

I have used Tyvek FlexWrap for cills and also for pipes through walls. Works well as it is elasticated enough to stretch around corners.

From my research when I was going to do timberframe that looks spot on what I would say is use a specific product for the cill pan, just wrapping your external membrane into the opening will not do, it needs to be fully waterproof. A lot of literature i read said a good belt n braces approach was to tilt your cill plate 5degrees down so any water getting to the cill pan gets gravity to pull it outwards.

I use ‘Nest’ Edited: just re-read your question. The Nest detectors link together via WiFi but I’m not sure if they act as repeaters

I think "making good use of" might be a bit of a stretch ?

But surely, if you have lived in the house for a year now, and given how long and not last summer was, the real life experience overrides all the software modelling? If you didn't fry yourselves last summer then is it really necessary?

I am doing a full renovation which will include cavity fill and external insulation, internal on front elevation as couldn’t get external insulation past the planners on the front.

Thanks for the mention Ferdinand...I've been busy and moved house with all associated hassle. The e-book you mention is still extant, but reduced to £5 from Amazon. I post occasional extracts on Facebook, but that generates limited interest! So it goes, so it goes. Cheers to you F

This isn't a flippant response. What's the end-in-mind? What does good use of mean? The answer to those questions can usually be written down in a simple problem statement of about 10 to 15 words. How well the questions are answered will be a key determinant of the quality of the site.

Have you read these albeit some are not very recent? I think many Facebook blogs for self builders seem to be closed groups as they tend to be more to keep friends and family informed than for public view. Industry wise some sites are pretty dire and hardly ever updated but the Scotframe one isn’t too bad. https://www.lexisclick.com/blog/builders-cracked-construction-industry-social-media https://www.pauleycreative.co.uk/2010/06/how-do-the-top-15-construction-companies-fair-on-social-media/ https://blog.feedspot.com/uk_construction_blogs/

There are several on FB and members here are on some of them. If you are on FB @Ferdinand I can invite you.

Why would you want to encourage the use of FB etc?

Certainly, they came from Conservatory Blinds Ltd and the model is the Duette Thermal conservatory blind: https://www.conservatoryblinds.co.uk/conservatory-blinds/duette-thermal-blinds/ Ours are in parchment, with parchment support bars.

More scientifically you need to look at the low for the month. So if you get the Met Office data for your area and look at the min OAT figure, you’ll see that January may be colder than December. I would expect to get to an average, there is a minimum that is 30-40% lower than the mean so you will have at some point a loss of 60KWh on a day. Running an ASHP for the 7 hours of the E7 period (assuming no solar) means you need around 8.3Kw/h input heat, so a 9Kw ASHP would do this with no peak usage. As @ProDave has said though, a 5Kw would work however there is no consideration for hot water provision. @JSHarris spreadsheet is much easier to use btw ..!!

So December needs 973.2KWh that is 31.39KWh per day or an average power 24/7 of 1.3Kw You probably don't want to run the heating 24/7 so assume it is on half the time it will need to produce 2.6Kw of heat for that time. A 5KW ASHP should do you comfortably.

Glutton for punishment, or inspired minor adjustment? Hmm. I can see the benefit, especially on the entrance route, and perhaps someone can give you a ballpark number for the cost of those foundations. Rather than a full sketchup, try just adding the new outline bits onto a printout or trace a plan onto a new sheet over with a pencil or coloured felt tip. An option for the hall-light would be glass panels beside the front door. Would you try and pull he garage inside the insulated envelop? You could do the hall and door and bay under PP, then leave the garage/gym for PD? Remember you only have 3 years to start . F

Use some white diluted vinegar and spray it onto the area and it will sort it out

Have you forgotten where you live ?? I would think it will all be ok when you get the doors open in August if your worried give them a wash down with a bleach solution and let the wind blow through.

With no expansion room at all, then the pressure will rise a very great deal with even a small temperature change. Water is, to all intents and purposes, incompressible under the sort of conditions in a heating system. A 70 litre volume system will try to increase in volume by roughly 0.3 litre for a 20°C temperature change, so with no expansion vessel, and ignoring the slight increase in system volume from the thermal expansion of the buffer tank and pipes, the pressure will increase by a lot, possibly several bar unless a pressure relief valve were to operate. My earlier guess of the PRV letting by around a cupful seems to be about right, too, at 300ml!

I think your plumber has nailed it. The pressure will rise in the sealed ASHP circuit as it heats up, and there should be an expansion vessel in that circuit to allow for this and limit the pressure rise. I see about 1/4 bar change in pressure between hot and cold on ours, but that's with an expansion vessel. Without one I suspect the pressure is rising to the PRV threshold and dumping a tiny bit (probably only a small cupful) which is then causing the pressure to drop a lot when it cools down.

Our PV has been running for a while now, and having switched to E7 I'm finding that far and away the greatest proportion of our purchased electricity is now at the cheap rate (around 8.5p/kWh). With the good weather we've been having lately the house has been "energy neutral" (i.e. not using any grid power) by around 09:00 each morning, and has tended to stay like that until around 16:00. Every day that "no cost" window is getting longer, and reducing the time when we are using full price electricity.

We are in a flood zone and I have used brick and med density block cavity with Celotex CF5000 rigid insulation. Internal partitions also med density block. Concrete floor with wood finish porcelain tile. Rendered walls on the ground floor. Non-return valve fitted to foul sewer. Electrics set at 1200mm from ffl.

I'm no expert on approaches to flood mitigation but thinking out loud I could see tea cosy approach being preferred over cavity. I think you would certainly want to avoid mineral wool in the cavity if there was a risk the cavity could be breached during a flood. The stuff takes an age to dry out once wetted (experience of dritherm32 batts left in the rain on my site) and when saturated tends to slump and deform. If going with EWI, then I would think an open cell insulation would be much preferred. EPS is open cell somewhat vapour open so in a flood the wall inside if wetted would be able to dry outward. Closed cell such as PIR or XPS I think would not allow this, you'd need to dry from the inside only. I think there are few system suppliers who specify closed cell EWI in any case. There were issues a while back with PIR boards used for EWI deforming once fixed, "pillowing" I think was the term used. Nearly all systems I considered were graphite enhanced EPS. There are some that offer wood fibre or mineral wool options but neither would be suitable where there was a risk of water immersion. I learned that EWI grade EPS differs from standard stuff. EWI grade it is cut from aged EPS blocks which are dimensionally stable. Standard EPS is not and there is a theoretical risk the boards could deform causing cracks.

You can get cavity wall insulation that goes in as a liquid and then becomes, effectively expanding foam. Aside from some of the obvious advantages, it fully waterproof and ones of its claimed features is for use in flood prone houses. So it would be full fill and flood proof. Arguably, you could just do the 1st meter, then normal cavity insulation from thereup. Its expensive! https://www.completeinsulations.ie/spray-foam-cavity-wall-insulation/

I think Tony's house (if we're talking about the same one!) is fully fulled wide cavity, similar to the Denby Dale passive houses. cavity walls as built new I think is still very much a standard and I think low risk in terms of later problems, the claims you mention will be for retrofit cavity wall insulation and damp issues (it's a complex topic) but this isn't something that put me off a wide fully filled cavity in my extension. Cavity walls aren't as popular with self builders, particularly passive houses. However it can be done well. solid wall is an option I considered. Mortgage-ability is a factor, you may need an eye on a future sale and there can be a bit of "computer say no" from lenders against single skin walls. Admittedly this probably isn't aimed at well built new houses with wide format blockwork, rather at single skin brick walls built last century which lenders consider structurally unsound. However, it may be worth exploring to check you wont get caught up in the same bucket. Wide format blocks and EWI would be my preferred approach for single skin. EWI can be employed achieving what is called the "full tea cosy" method - a continuous insulation layer from footing all over the house, including roof (using warm roof approach). You can completely eliminate structural cold bridging. EWI can be rendered, timber clad (or any cladding - zinc, through coloured cement panels, etc) or even faced with brick slips (these are effectively slithers of brick applied like tiles with a mortar applied rather like grout). I have seen some high spec examples that looked incredible and you would never have guessed they weren't brick walls. IWI is a bit of a headache with condensation risk behind the insulation, and the issue of creating cold bridges with internal structural timber piercing through the insulation layer to the outer structural wall. It's typically a retrofit approach, not sure I've ever seen it employed new build.

I think you need to approach these two through your wider design goals rather than as more standalone questions ... how much heat storage capacity do you need in the structure, and what is your planned route and method for letting any moisture out of your walls. That in turn depends on the type of structure you select, and interplays with it. You need to be looking at thermal spec, decrement delay, and so on. eg for EWI it will impact o; permeability and wall thickness whether you choose PIR or EPS. Ferdinand

Try googling 'Tony's house reading' for an example of a solid walled house. If there is a significant flood risk how will you manage it - raising the ground floor? will it be insurable?

Why not look at ICF then? In effect you have solid walls with the insulation all in place?

You can go with a single skin option using blocks on their flat and combine this with external insulation which you then render what ever colour you want which will then be waterproof. The problem with using bricks is they aren't waterproof so will pull water in towards the house, hence a cavity would be needed to stop the damp going all the way in. With blocks they will store the heat and then slowly release it back.