Marvin

Hi and Welcome @Helicopter_red Its great to work on obtaining the best from what you have! If this is going to be a 'Done Roaming' property like ours then I assume you have considered improving the function as well as the form. We worked hard on improving the ergonomic use of our building for now and the future. Efficient energy use improvements can be gifts that keep on giving! (After filling in unnecessary holes, and insulating the loft properly in my brother-in-laws house he is already using 20% less gas a year for the same heating effect.) Good luck M

Hi and welcome @newhouse87 It sounds like your doing the right thing by testing - trial and error! It's a process that requires patience to get right. Personally, I would turn on one room thermostat at a time and check which actuator reacts, which flow and return pipes at the manifold become hotter and which area of floor warms up. This can take some time..... Only then can you be sure of what you have and then consider the remedy. Good luck M

I always install a Pressure Reducing Valve on mains. It saves all the equipment from straining / wearing faster. I have worked on properties where the overnight pressure is 6 bar and during the day 2.5 bar wandering to 6.

Hi @ProDave 😆😆 Just wait. People are using less power.... We differ on the grants. The more the "kind government" dishes out the more in debt WE become the more interest WE will pay, the more TAXATION we will face in the future. The more in debt WE become.

Here comes the fear..

Hi @PeterW So a £200m loss selling the power and a £1,200m profit producing the power. I won't cry for them yet then.... I make a 100% loss producing quotes and a profit from awarded contracts. So What!

Why are we paying so much for electricity? Here's one answer: https://www.bbc.co.uk/news/business-64647854

Warm roof!

My guess is 44C

Hi @Terryt Welcome I'm sure there's someone here who has some experience with this sort of thing.

Plus 1 about the loo!

Hi @sylvane Welcome Bit concerned that you will find it difficult to convince Building Control that thinner insulation will pass the requirements. What's the width of the bedroom?

Hi @Larsen Welcome. I know the feeling!!!

Any use: https://www.thorenvarmepumpar.se/images/Pdf-er/users_manual_thor_es-3.pdf

Hi @SDTM Don't know if any of this helps... https://www.varmepumpsforum.com/vpforum/index.php?topic=46451.0

Someone with sense!

Hi @Jimmyjazz Welcome. Always good to have other's thoughts on a projects. We gave up finding a site and went the renovation route. 🙄 I don't know if will ever get to adding to this site as much as I have learnt. I doubt it!

Aim to go APE It worth considering all the AIM and APE elements before making decisions. That is Airtightness, Insulation, Mechanical Ventilation with Heat Recovery OR Heat pump Ventilation, and Air Source Heat Pump, Photovoltaics and Electric Vehicle. Some of these will not work properly without the others, and some will complement others: A MVHR will not work properly without Airtightness. An Air Source Heat Pump will have to compensate for the lack of Airtightness and/or Insulation to the degree that the benefits become questionable, especially during winter, without them. An ASHP uses electricity and Photovoltaics can supply a little during winter and a lot during summer when cooling can be a problem and an ASHP can supply cooling. PV can supply a little to an Electric Vehicle during winter and plenty during summer if your vehicle is at home during sunny days. Extending a property and only doing AIM works to the extension will be no good, you have to do all the property within the thermal envelope. And thinking of running costs: a) Airtightness and Insulation should have no running costs and last (Well, loft insulation lasts over 40 years, in our experience) with the exception of UPVC units for windows and doors, but that being said it will last 30 years? b) Our MVHR unit servicing 100m2 floor sized home uses about 260kWh a year; far far less than would be used to heat incoming cold fresh air in winter, and we clean the filters twice a year. c) ASHPs are, in my opinion, still in their infancy but we are now in the second year of use here. We were very careful to follow best practice in the design and installation of our system, did a lot of bespoke tweaking, and we now have an upgraded 1970’s timber framed bungalow that uses less than 25kWh per year per m2 of floor for heating. d) PV would be a lot less attractive if there is no ASHP or EV (or battery backup) or diverter to the hot water immersion. In my humble opinion, if you have a suitable roof you should install as much a physically possible. Electricity production costs (cost per kWh) are difficult to evaluate because it depends how much is used and how much is supplied to the grid. We decided to go with the PV cost divided by 7 years, which for us works out at £1.60ish per day. Yesterday the PV produced 12kWh all of which we used. Remember, 5kW of PV panels will not produce 5kW because you would have to have: i. No shadowing of any of the panels during sunlight hours (like trees, buildings or chimneys. ii. All the solar panels face exactly the right angle in relation to the summer solstice midday sun for their position on the planet. (Perfect angle facing south and perfect slope) iii. solar panels completely clean iv. the sun is completely unobscured v. the Inverter is 100% efficient vi. all the other losses due to cables, and equipment, and so on. e) Knowing the above PV limitations professional installers often add extra panels to make up for these losses. (Our inverter allows us to add roughly 28% more panels than its kW rating) f) PV panel installations will produce about one sixth of the power in the winter compared with what is produced in the height of summer. g) The electric vehicle and charging from the PV only really works if you can have the vehicle plugged in during the day and supply over 3kW from your PV (or a large proportion of that). This is why we went for the biggest PV that would fit on the roof. We then installed a system which only charges the when the PV is on and generating over 2kW in winter and 3kW in summer. (we have a 13amp charging system). So, if finances cause you to have to consider only a few in my humble opinion AIM first and go APE later. (But prepare the property for the APE works as much as you can). Best of Luck Marvin

Hi @John Jackson No ours is a cold loft but the insulation covers the tank. Yes it's the mix of water sitting for ages and the warm temperature that causes the problem. That's why I only have a small tank and refill it at the end of the day. When completing legionella risk assessments, water sitting in lofts for a long time was one of the problems. We had to make sure that any water connection changes that had been done over the years, removed all defunct pipework, that was still connected. Some buildings had long pipe runs to nowhere leaving water to stagnate for years causing a risk especially with mains water.

Some info: https://www.sciencedirect.com/science/article/abs/pii/S2352710219330190

Most PIR for floors has the same sort of thermal resistance so your really only discussing thickness. I would go for as thick as you can stomach! As @Nickfromwales says save you every year!

I think you will need to replace the lintel. It has to be supported at both ends by at least 100mm so needs to be at least 35 inches (890mm) wide central over the new opening. I like to go 5 to 6 inches each end...

We use an unvented cylinder with no problem....

I think you would only need a header tank that will hold about 2 days water at once. Ours is about 60 gallons. We only use rainwater for loos. held in a underground tank with the header tank filled daily and therefore doesn't sit long in the loft. However we do not use it for washing machines and only pass it through a sand filter.

Hi @Post and beam As @Kelvin says, not difficult to understand once you get your head around it.