Keeping your home warm / heating / energy crisis / insulation etc

I went to a interesting academic talk a while back about how people interact with heating in houses. The speaker noted that the expectation that you could be warm everywhere in your house is a fairly modern conception and that in times past you'd have a warm spot by the fire and in the kitchen and a warm bed, but you didn't really dwell anywhere else. That's not to say that being cold is charmingly Dickensian (it's just shit if it's not of your choosing), but makes for some interesting thoughts about how we might use our living spaces in a different way.

Reading reviews now. We're in a turn of the century Colonies terrace, awful single glaze sash windows, lots of floor boards. We get a fair bit of condensation on the windows in Winter.

Is this Dehumidifier as good as the reviews say for drying clothes indoors? I've also seen people mentioning they don't have to have the heating on as often too?

I read something recently on another forum and saved it for reference as we’ve just moved into a new place that I suspect will be expensive to heat -

“This is a tricky topic - but something I've been very involved with over the years - we run a Chartered Survey company, and I've written the book on dampness in homes - and the effect that temperature has on the building fabric. I'm sure Martin won't mind me mentioning the name of the book - its out on the 17th Sept, and pre-orders are being taken - called The Warm Dry Home and available on our website - just look for the Heritage House website.. (I'm not sure about the admin rules for posting links) So, back to the topic.

A warm house is a dry one. For a house to be dry, it needs to be warm enough that condensation doesn't form within the building fabric. That means the walls and structure have to be kept above the Dew Point - the temperature at which condensation occurs. Its not something that just forms on surfaces - it forms within the walls, which is what that old fraud of rising damp is about - moisture condensing in brickwork or stone. Where does the moisture come from? Mostly we humans - living, breathing, cooking, showering. It has to go somewhere, and most houses are NOT well enough ventilated - so moisture is able to settle within the fabric - it passes through it as a gas, but if that gas is cooled down below Dew Point, it condenses, and is held in the walls and fabric as water.

A damp wall transmits heat much quicker than a dry wall, so house gets colder and damper. How do we stop this happening?

We make sure the building stays above a critical temperature - we have a guideline of 15 degrees C., at an RH of 50% - and total moisture content of 7 grams water per cubic metre of air. That's about a teaspoon. Given those parameters, the Dew Point is about 4 degrees C. So you wont get damp, and the house stays dry.

So - how does this relate to the OP? When to turn heating on? You turn it on in such a way that you don't allow the FABRIC of the building to drop below 15 degrees C. You keep it on - constant low temperature heating is cheap to run, and ensures you keep a DRY house, so long as it is well ventilated. I can't emphasise enough that for all this to work you need to ventilate - humidity controlled extraction in kitchens and bathrooms is a must.

So when night time temps start to dip below 15 degrees, you need to get the heating just ticking over, to maintain temps at the right level. Its not about when, so much as 'what are the temperatures'.. In ALL rooms as well ! Don't leave some rooms with heating off - they'll just get mouldy and manky.

Make sure you also check the building - guttering and downpipes work, drains are clear, there are no cracks allowing water into the ground and soaking the soil at low level - ground levels externally are 150mm below internal floor levels.

All of this promotes dry walls, and thus best chance of maintaining a warm home - which wont lose heat nearly as quickly, and cost less to heat. Remember - it costs a lot more to heat damp air than dry air. “

This is brilliant, thanks for sharing 👌

Quite possibly.

But even less likely is that they make inferences about your energy usage estimates, such that you pay any amount at all at the current lower tariff.

im not sure how effective a dehumidifier will be if your house is as leaky as you describe (could struggle if outside is more humid and the air keeps getting replaced)

However, in our place, which is a victorian terrace with double glazing, a dehumidifier was the best thing we've bought. Clothes dry out quicker, no condensation, far less damp etc. Our kitchen extractor fan doesnt vent anywhere so this also helps bring the humidity down after cooking.

That means the walls and structure have to be kept above the Dew Point - the temperature at which condensation occurs. Its not something that just forms on surfaces - it forms within the walls, which is what that old fraud of rising damp is about - moisture condensing in brickwork or stone.

This is really interesting, since a common recommendation is to fit internal insulation. For example, this is being recommended to us because the cavity in our walls is pretty nominal (~50mm). The downside is that the inner leaf of blockwork then doesn't warm up so the dewpoint moves inwards. I've read people on here saying how good they felt that interior insulation is, but I'm interested in whether this effect can cause an issue and reduce the benefit of the existing cavity.

We're in a Victorian end of terrace. It's got shit double glazing and appears to have a decent amount of loft insulation but I suspect the big wall with no house next to it and not getting much sun doesn't help.

In the living room for the past day:

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I've got a wooly hat on. Will be putting up the hairdryer 'double glazing' this weekend.

This is the ridiculousness of our front bedroom.

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Yes, it is great, we don't have an option to dry clothes outside and it helps massively.
As I mentioned before I also use it in the bathroom before taking a shower to dry the air out.

A number of factors could be at play here, difficult to assess from a graph.

Do you have a live video feed to your bedroom?

Asking for a scientist.

Temps around our flat for last 7 days. No heating has been on at all yet (actually, looks like it might have come on at about 6pm yesterday, thermostat is set to 17 deg C.)

A couple of computers in the "study" hence the slightly higher temp there.

(The red line at the bottom is in the shared hallway outside the flat but still indoors.)

We dry clothes inside regularly (the garden is a long schlep) and so we use a dehumidifier. It's modern but not I'm not 100% worried about its efficiency as any inefficiency is just output as heat.

Nothing much else we can do. We have neighbours downstairs and upstairs. If we ever rewire we'll need to pull lots of the carpets/floors up so we'll add some insulation (mostly for sound) that might help a bit. Only one set of windows (living room) aren't double glazed. But essentially it's a big Edwardian house cut up into flats with no real/proper ventilation adjustments.

Good news is that next week should be warmer (highs of 20 deg C at some point in Londonton). Also may have overestimated my gas meter reading back when the price crisis first started - can't do that with Electricity as it's a smart meter.

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Here’s a room in our dull but efficient modern wooden house yesterday. No heating on, unoccupied all day. It has three external walls facing north, south and west with two pretty big (albeit triple glazed) windows.

Outside temp was between 9 and 16 degrees.

We’ve got 140mm of PIR insulation in the walls and roof and 100mm in the floor.

Insulation works yo.

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There's a couple of things - one is efficiency of running the home eg damp walls conduct more heat to the outside, the other is how temperature, humidity and damp (condensation) are connected. These affect ambient temps and humidity, which are really important. Thermal comfort (how you feel) is also influenced by other things - a really significant one is radiant heat - if the surfaces in your line of sight (your body's thermal line of sight, really) are cold, you will feel colder. If they are warm you will feel warmer. Internal insulation provides a warm surface. It also improves overall thermal efficiency (less heat lost to the outside), so whatever heat you are inputting leads to warmer temps. The big thing to watch out for is interstitial condensation between the warm insulation and the cold wall. The existing cavity will still be doing a job to prevent damp from the outside getting to the inner leaf, and it will still be doing a job of reducing heat loss but much less significant compared with the new insulation.

Edit to add: In the summer, another thing to consider is that internal insulation covers up your thermal mass, so overheating is more likely to be a problem - not because of the insulation but because you lose that exposed thermal mass which acts to buffer heat gains.

Edit to add: In the summer, another thing to consider is that internal insulation covers up your thermal mass, so overheating is more likely to be a problem

How does that work? Presumably overheating is due to too much heat moving from outside to inside. That process would be slowed by internal insulation. It might stop temperatures equilibrating overnight (assuming that the outside temperature drops below that of your house), but I'd suspect it's more important not to allow your house to get too hot during the daytime in the first place.

I'm getting swamped and now there are I WhatsApps going around about submitting reading today.

Is this something I should be finig time to do today ?

Cheers.

Do you have a smart meter? If so, then no. If not, then maybe.

If you think the supplier is overestimating your usage, probably just leave it

If the supplier is underestimating, provide a reading

If you are still on a fixed contract then just carry on as normal

External is much better but more spendy.

External not always more expensive. It's also much less disruptive to you living in your house.
At some point I'll need to internally insulate the side wall as I don't own the land on the other side, but it'll be a massive pain (it's the wall with kitchen, bathroom and stairs up against it).

What is giving you (and others) the nerdy temp graphs? I assume some kind of tado/nest smart thermostats on rads in each room? I feel left out.

Looks like Grafana (on HomeAssistant maybe)

That’s it. The central heating control system, Wi-Fi or hardwired thermostats(s) and an app. Mine’s https://www.heatmiser.com/en/

It’s hours of fun for all the family.

See how I opened a window at 7am for a bit of chilly fresh air, then had a shower at 9pm:

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