heating system for a new v well insulated house

romeonovember

hi there,

we have submitted PP Application for 2900 square foot split level house last week. we are planning for circa 300mm EWI fixed to block on the flat to give a u value around 0.1. the blocks will be wet plastered on the inside to give the air-tight layer. we are going for as good of triple glazed windows as we can afford, ideally something passive. we are going to go for a passive slab for the foundations, and v well insulated roof. Our problem is that we don't know what heating system to go for. I am thinking of solar for the summer hot water, and the winter is my conundrum. I like geothermal, but don't really think it would pay-back to install it with UF heating in a super insulated house. we plan to have a insert stove in the living room which could have a boiler that would heat a buffer tank in winter, with another free-standing stove in the kitchen/diner/den area, so UF heating would be a waste of money in these locations. we were thinking of a heat source that would power radiators in the bedrooms, entrance lobby and towel rails in the bathrooms, so would an insert stove with back boiler be sufficient to heat these spaces - circa 1700 square feet, and provide winter hot water? another option would be to install a multifuel boiler in the garage and use this in winter with a v large buffer tank and then run the heating system out of the buffer tank. we live in the midlands so there is no shortage of good turf, with access to timber from the farm. Apologies if these seems muddled, its just that there are so many different technologies out there.

kscobie

First, build a shed, run a well insulated heat pipe to it from the house, and that allows you to have many options. You mention you have solid fuel, but this is how you will heat your house from now on, the attraction will wear off in a few years.
Geothermal or air source heat pumps must be correctly sized, but I personally don't like them. Some of the lads here will have a preference for one or the other, and will be able to guide you on this.
I have now fitted a few of the Grant pellet boilers, and are both efficient and reliable, just use the proper pellets. I seen a prototype of their new little pellet boiler at the Ploughing Show last week, 4-16kW, and is the job for new well insulated houses.
To be honest, whilst it wont comply with the new regs, a small gas or oil boiler would be the best due to the small heat load, but we must comply:o

MicktheMan

romeonovember wrote: »

hi there,

we have submitted PP Application for 2900 square foot split level house last week. we are planning for circa 300mm EWI fixed to block on the flat to give a u value around 0.1. the blocks will be wet plastered on the inside to give the air-tight layer. we are going for as good of triple glazed windows as we can afford, ideally something passive. we are going to go for a passive slab for the foundations, and v well insulated roof. Our problem is that we don't know what heating system to go for. I am thinking of solar for the summer hot water, and the winter is my conundrum. I like geothermal, but don't really think it would pay-back to install it with UF heating in a super insulated house. we plan to have a insert stove in the living room which could have a boiler that would heat a buffer tank in winter, with another free-standing stove in the kitchen/diner/den area, so UF heating would be a waste of money in these locations. we were thinking of a heat source that would power radiators in the bedrooms, entrance lobby and towel rails in the bathrooms, so would an insert stove with back boiler be sufficient to heat these spaces - circa 1700 square feet, and provide winter hot water? another option would be to install a multifuel boiler in the garage and use this in winter with a v large buffer tank and then run the heating system out of the buffer tank. we live in the midlands so there is no shortage of good turf, with access to timber from the farm. Apologies if these seems muddled, its just that there are so many different technologies out there.

That's a very interesting building fabric spec but first things first. Have you had anyone do a phpp calc to work out the heat load accurately? Also what air tightness target are you aiming for and have you considered an appropriate ventilation system? Will thermal bridging be eliminated?

If the above is done properly, an air to water hp combined with solar PV linked into the grid might be a good choice for your heating / dhw needs as well as compliance with renewables in part L.