Jeremy Harris

Not sure about this. I planted ~10 trees this time last year, and if we end up inside the CA (which seems possible) then that means I need to apply for planning consent just to prune and manage them, every time I choose to do so. It also means I can't erect anything without consent, too, as it effectively takes away PD rights.

I'm not sure there's any benefit from living in a conservation area. I'd say that most buyers would view a house in a conservation area as being an additional liability, as PP is needed to do as much as prune a tree in the garden, let alone do anything as radical as replace a window. The added maintenance costs of any property within a conservation area can be pretty high, not only from the cost of all the planning applications that need to be made, but also because of the restrictions imposed on the materials that may be used.

On the point about adding a cooler on the MVHR intake, this seems not to make sense unless the MVHR has a bypass function. For practical reasons, associated with trying to retrofit a duct cooler to an existing installation, I'm planning to add one to the outside intake of our system. This will just be connected to the ASHP flow and return and includes a motorised ball valve that only allows flow through the cooler when the ASHP is in cooling mode, and already cooling the floor.

We do have a vented cavity behind the skin, so that will reduce the heat transmission a fair bit, but I've no idea how to try and model it. I could try and poke a temperature sensor into the cavity and see how warm it is in there, as that's probably closer to the temperature of the outside skin of the insulated wall itself. I might have a go at doing this tomorrow, just to see how effective the ventilated space is at reducing inward heat transmission.

I hate to say this, but I opted to just cut down the trees on our site as soon as we purchased it, and before we submitted a planning application, because I had a feeling that objectors might well just get TPOs put on them in order to block us. I had a couple of complaints at the time, but there wasn't anything they could do after the event. Anyway, I've now planted 10 new trees, plus a few hundred native hedging plants, so have more than made up for the loss of a couple of horse chestnuts and a sycamore. Also, according to the EPC, our house has a CO2 "emission" rate of -0.9 tonnes/year, it's roughly the same as having about 42 trees on the site, and I doubt that 42 trees would fit.

It seems that the planning portal has been contracted out to TerraQuest, who are presumably now trying to make a profit from providing this service: https://www.gov.uk/government/news/new-partner-appointed-to-run-the-planning-portal The appointment was made some time ago, but presumably it's taken this long to get their payment scheme up and running.

I was intrigued enough by this to pop out and measure the temperature of the outside wall of our house (just outside the front door, so facing SSE). It's currently (at 17:40) sitting at 36.8°C, so about 15° warmer than the inside of the house.

Decrement delay (in hours) is the time between the peak temperature on one surface of a wall or roof and the peak temperature on the other surface. In general terms, it's the time taken for heat to travel through that part of the structure. It's dependent on both the thermal conductivity of the structure, the thickness of the structure and the heat capacity of it. A long decrement delay will be given by a thick wall (or roof) with a high thermal resistance (low U value) made from material with a high heat capacity.

My one and only experience with NHBC was dire. We bought a new house (had been the show house on a small development, so was really 2 years old) and about a year later started noticing water stains on a bedroom ceiling. Investigation showed that water was getting in around the chimney breast. NHBC tried every trick in the book to get out of paying, and in the end we got our lawyer on to them. We paid for an inspection, with clear photos showing that the lead flashing had been fitted by an idiot (the overlaps were the wrong way around, believe it or not). Despite the hard evidence of the defect, NHBC still refused to sort it, and in the end our lawyer suggested that it would be cheaper for us to just get the flashing fixed ourselves, rather than continue to try and pursue NHBC. We concluded that an NHBC warrantly wasn't worth the paper it was printed on, and vowed never to have anything to do with them ever again.

It can be worked out from first principles if the conditions are known, but one problem is that often the conditions aren't known accurately enough to make modelling that useful. One way to try and measure it is to look at thermal admittance, which is a measure of the ability of a material to absorb and release heat into the interior of the house. However, accurately assessing this is compounded by the way that we tend to have most of the internal structure in a house (at least the part that can act as a thermal buffer) made up of layers that have widely varying thermal conductivity and specific heat/heat capacity. Plasterboard is a good example, as there is a large area of it on the inside of a house normally. It has a specific heat of around 1.09 kJ/kg.K, so for a skimmed plasterboard wall each m² will store around 10 kJ of sensible heat for a 1 degree temperature increment. Taking our house as an example, it has a total wall and ceiling area of around 600m², so the plasterboard and skim will store around 6,000 kJ, or about 1.66 kWh, of sensible heat per degree change in temperature. The plasterboard/plaster skim contributes a fair bit to the thermal buffering effect The challenge is then to try and work out how well any surface in the house will transfer heat in or out of the house. Materials with a high thermal conductivity will tend to do this more quickly than materials with low thermal conductivity. it's not much use having a quantity of high heat capacity/specific heat material in the house, but buried behind layers of material that have a low thermal conductivity.

Of course it isn't. Heat capacity is the physical property of a material that defines how much sensible heat it can store per unit mass (or volume). Thermal conductivity determines how well heat flows through any material. Both of these properties can be measured and have defined units. Thermal mass has no units, so how can anyone measure it, or define what is "high" or "low"?

Like all other supposed explanations for this mythical physical property, it fails because it doesn't define the units of measurement. As mentioned many times, we can measure and quantify heat capacity, thermal conductivity, decrement delay time, thermal time constant, temperature etc, but no one has yet invented any units to define thermal mass (hardly surprising as it doesn't exist as a physical property). The graph (figure 1) showing the stabilising effect is nothing to do with "thermal mass", it's just a consequence of having sufficient insulation, with a long enough decrement delay, to damp and offset the time taken for the inside of the house to change relative to changes in outside air temperature. This is aided by having a means of storing enough heat in the internal structure (and then only the first 100mm or so of it), in a layer with a reasonably high thermal conductivity, that can act as a buffer heat store.

I'm pretty sure it's now common practice to install eaves vents and a ventilated ridge, as when we were looking through various manufacturers installation instructions most seemed to stipulate some form of under tile/slate ventilation, with many providing proprietary solutions. Our roof has counter battens over the sarking, with membrane and slate battens above that, so that there's good ventilation from the eaves, up under the slates, to the ridge vents.

If you want to slightly reduce the geometric thermal bridge at the junction it might be worth making sure that the roof insulation projects slightly outside the wall. That creates a longer heat loss path, which may compensate slightly for the effect of the geometric thermal bridge. I did this all around our house, I added extra rigid insulation into the roof overhangs at the eaves and gables, all foamed in place.

As above. If the topographic survey has been done in the normal way then the spot heights marked will be in metres above Ordnance Datum (the mark on the harbour wall at Newlyn, Cornwall) and the letters by them should refer to the base of a feature, usually something like a tree, post, etc that's on the ground. There may be a key (with luck) showing what each point reference letter, or letters, refers to. For example, on our survey TP = Telephone Pole, T = tree, FP = fence post, etc. With luck you should be able to find some fixed reference points on site to work from. Usually a topo survey will be done from one or more baselines, with defined end points, and these form the horizontal plane datum from which the other spots are measured, so if you can recreate the baseline then it's easier to set out from it. Often it seems to be a matter of luck as to whether there are any fixed points left on site to work from, though. In our case we were lucky, in that we had an Ordnance Survey spot height nail in the lane just by our drive, and this was used by our surveyor as one end of his baseline, with an orthogonal offset from a telephone pole used as the other end of the baseline. It was then easy to just reference every measurement back to that to set out the site and get everything in the right place.

It surprised me, but as one of our ground works chaps said at the time (when we were all moaning about the crap service from OpenReach) you get the service you pay for... In our case the wire over the top of the plot was connected to an SSE power pole that had been replaced in a new location by SSE, leaving just the 'phone wire on it. Apparently OpenReach are obliged to move over-sailing wires free of charge if they are causing an obstruction, as this wire was.

FWIW all OpenReach work done at our site was free of charge, too. They supplied Duct 56, cable, hockey sticks, cast iron boxes etc all free and did the reconnection and cable move work free.

@Russdl, PM sent

We found that a memory foam mattress was just too hot at times. My wife found it very uncomfortable back when she was regularly throwing the bedclothes off in the middle of the night, complaining that she was really hot. Since switching back to a sprung mattress things have been a lot better. I strongly suspect that the memory foam just doesn't allow enough ventilation, plus it's too good an insulator. It was also damned heavy.

We had a real problem getting OpenReach to move a wire that was running over our plot. Getting them to agree that we could put it underground in Duct 56 that they free-issued was relatively easy, but actually getting them to take down the overhead wire and connect up the new underground one was a PITA. In the end we used subterfuge (at the suggestion of a local OpenReach employee) where we "accidentally" took the wire down early one morning, with the aid of the digger jib, then phoned their emergency number to report the wire was down. They sent two chaps out straight away, and when they arrived on site we just pointed them to the new cable neatly coiled up at the base of each pole, they grinned, mentioned the name of the local OpenReach chap and then set about just connecting up the new cable. The whole job was done in about 30 minutes or so. I don't know if the local chap I knew is still working for them, or whether he's retired, but as you're in the same area I could PM you the phone number I had for him back then. He was really helpful, unlike his management...

The level turning area outside the door is really important. My friend came around to test our access for us, and advise on whether or not we'd got things right indoors, and in the loo, and he mentioned that it was a nightmare trying to turn a wheelchair through 90 degrees and lean forward to open a door if there isn't a reasonable sized flat space available outside the door. He also pointed out that he needs room to be able to reverse his chair as the door opens, so there needs to be enough flat space to allow for that.

I've never had a problem with the Philmac ones either. They always seem to be as reliable as the Plasson ones to me, but then again pretty much every MDPE fitting I've used has been OK, with the single exception of one pale blue one that I think may have come from Screwfix.

The difference is between routine functional testing of the RCD, which only tests the functionality of the RCD/RCCB/RCBO itself, and installation testing, where using a tester that creates an imbalance by shunting to earth more or less tests the real-world protection the RCD/RCCB/RCBO provides for the circuit. The evidence available suggests that routine testing of RCB/RCCB/RCBOs tends to increase their reliability (perhaps by just exercising the mechanism and reducing the risk of mechanical jamming?). Testing an installation isn't such a regular exercise, typically it would be done every three to five years, rather than every six months for RCD/RCCB/RCBO functional testing. The installation test is more realistic, as it simulates what might happen when leakage develops between line and earth, so it will reveal a very high resistance, or open circuit, PE, as when tested like this the RCD/RCCB/RCBO won't trip. The routine functional test won't ever test that; it will only show whether the RCD/RCCB/RCBO is working as designed (more or less - it doesn't test the time taken to disconnect).

The test button built-in to an RCD/RCCB doesn't usually connect a resistor to PE, it connects to the neutral on the other side of the sense coil. This means it can test for functionality without needing a working earth connection.

Yes, I fitted black PVC boards over the EPS, and then used coarse gravel to fill the gap between the house and the patio or paths. Under the gravel is a layer of terram covered with whacked down MOT1 (just the same as the sub-base for the patio slabs and path pavers/stone slabs). Seems to work OK.