Building a house

[trueblue1234]

Anyone know much about mechanical ventilation and heat recovery? Been advised to put it into our new build by a friend who's in the construction business (just advising he's not commercially involved). But would like to get a second opinion?

[Hereiam]

Not sure if the initial cost is justifiable true blue. U could spend 3-5k on a system and the payback is 10yrs plus. The best thing about is that u will always have a fresh air feel to the inside of the house. The main expense to these systems is the ducting. If ur only at drawing stage u could be smart and plan the routes and make the ducts out of plywood/plasterboard.
If u are building timber frame it would useful as these are more or less buikt air tight so its a good way of gettin air in an out.
In my own house i put a drimaster (piv) in my roofspace which puts filtered air down into the house via a ceiling vent. Does the job.
Building regs are due to change and they will be tightening up on ventilation so it looks like a whole house heat recovery could be made the minimum standard.

[trueblue1234]

Cheers Hereiam. I've been told that in order for it to work right we need to be building to passive house standards (I think that was the term). The benefit for us he reckoned was that we could put underfloor heating in downstairs in some of the rooms (Basically the tiled rooms, 3 in 1 and halls) and that we wouldn't have to put radiators in the other couple of rooms (Living room and toy room) as the MVHR system would transfer the heat. Thought that it would be a bit of a risk but he seems to think if done right it's the way to go.

[Hereiam]

If u think about what he is saying. Using one area of a house to provide heat from the underfloor and then transfer it to the other rooms. Waste of time, unless there is alot of solar gain ur still gona be using oil to heat the other rooms. Ur room stat will always be calling for heat.

[Tony Baloney]

Sounds like rubbish to me unless the mhrv is going to reheat the drawn air from the rooms with the underfloor. You'll never transfer heat from one area to the other through ductwork without heat loss so those rooms will always be colder. I thought the primary benefit of MHRV was to recover the heat from already warm (higher than ambient) air e.g. from bathroom and kitchen extracts.

[trueblue1234]

I have my doubts about it as well. But there's plenty on line about it. I found the below on another website that were discussing it.

Payback is important but there is other benefits that are of interest as well.


<sup>pros.
1. controlled ventilation system independent of outside wind and pressure.
2. Air quality and filtration.
3. steady stable heat delivery.
4. Humidity reduction (very important for Ireland with av RH of over 80%
5. Heat recovery.
6. Can deliver heat through the ventilation system for near passive spec. removing the need for radiators, you can just put some underfloor in tiles areas and maybe a couple of towel rails and the MHRV will distribute
7. can run at multiple speeds depending on occupancy c02 meters.
8. Feels fresh inside.
9. Cost neutral over 4 years.
10. New part F ventilation requirement means 4% bigger hole in wall vents.
11. can halve space heating bills.
12. adds future proof value to house, even if you just install the ducts now, as if you sell it in ten years, the market will want MHRV.
13. Improves BER asset rating if combined with airtighness below 3 ach@50pa

cons.
1. Cant use open fire must use room sealed stove( why would you use an open fire)
2. Filters need cleaning twice a year (suppose you cant do that with your lungs0
3. perception of risk of mould growth in ductwork. This is due to early installers using flexi's for main ducts instead of metal ducts. However generally if ducts are insulated where fresh air is brought in, mould cannot happen because of reduced humidity.
4. dosent work with our speculator based construction methods of build it cheap and feck off. Therefore hole in the wall vents seem more economical at build stage when occupancy costs are ignored.
5. Most self builders use substandard designers and builders who dont understand that energy efficiency can be incorporated at zero cost with a little bit of planning. For bolla sake, lettin engineers design houses! madness. Moreover to be a builder in Ireland all you need is a Navarra and a mobile phone, a plumber needs a four year aprenticeship and his papers.
6. Only makes sence to homebuilders as part of an integrated systems approach to building comfort. Dosent work for eejits who throw up a building reg standard house with chimneys and vents. 'oh i've only got €240k to build my one off, that means I can only go with cavity with kingspan, chimney, wall vent, massive oil boiler, 3000 square foot, with corridors everywhere. maybe stick on a ecobling heat pump to an inefficient house.' The problem is our designers and builders havent a clue. The people building efficient passive or near passive houses are self builders who have gone and done the research themselves and realised that spending on insulation and airtightness instead makes sence.</sup>

[supersarsfields]

Building a new house now as well and have been looking at alternatives to oil. Seems to be a lot of talk about this Air source Heat Pump. It's a bit like the Geotherm but less complicated as it doesn't require any ground work. Expensive enough to put in (Although there's a £1700 grant at the minute). Just wondering if anyone has experience of them or knows much about them?

[93-DY-SAM]

I've a gas fire in the living room which is a waste of space. Nice to look at but about as useful as a chocolate teapot. Was thinking about ripping it out and installing a solid fuel stove. Was also thinking about possibly linking this into the tank in the hot press to generate hot water and maybe driving a few radiators to give the oil burner less work to do.

Anyone experience of doing this and how'd you go about it?

[Hereiam]

A range of factors with this one:
Bungalow or two storey
sq.ft of house
How far is your HP from the stove
How many rads
Is you current plumbing a pressurised system or gravity feed
Age of house

My advice is get a dam good plumber and go from there. This is something you dont want to mess about with

[johnneycool]

A range of factors with this one:
Bungalow or two storey
sq.ft of house
How far is your HP from the stove
How many rads
Is you current plumbing a pressurised system or gravity feed
Age of house

My advice is get a dam good plumber and go from there. This is something you dont want to mess about with

In the north its a no no to have a stove with a back boiler into a pressurised system, it has to be an open vented system to dissipate excess heat as you just can't turn off a stove. There is a way around it with a neutraliser link up system;
http://www.dunsleyheat.co.uk/neutralizer.html

As for the rads, your stove will have a KW rating to room and to water and some will tell you the number of rads approximately, but from my experience a stove with a back boiler doesn't throw the same heat out into the room as you'd hope. To compensate a bit for this, keep as much of the flue exposed as possible as there's some heat comes off it.

[93-DY-SAM]

A range of factors with this one:
Bungalow or two storey
sq.ft of house
How far is your HP from the stove
How many rads
Is you current plumbing a pressurised system or gravity feed
Age of house

My advice is get a dam good plumber and go from there. This is something you dont want to mess about with

In the north it's a no no to have a stove with a back boiler into a pressurised system, it has to be an open vented system to dissipate excess heat as you just can't turn off a stove. There is a way around it with a neutraliser link up system;
http://www.dunsleyheat.co.uk/neutralizer.html

As for the rads, your stove will have a KW rating to room and to water and some will tell you the number of rads approximately, but from my experience a stove with a back boiler doesn't throw the same heat out into the room as you'd hope. To compensate a bit for this, keep as much of the flue exposed as possible as there's some heat comes off it.

Cheers lads.

House is two storied and about 2200sq ft. 
HP is on 1st floor at opposite side of the house from the fireplace.
It's a pressurised system and have oil burner driving abou 11/12 radiators of varying sizes of it. 

Have heard that before about back boilers and pressurised systems but thought there was some kind of release value could be fitted to this to manage that. Have also read that about the heat not being the same with the back boiler as the heat that would normally be thrown out is now being used to heat water. Want to make sure I know all the facts before jumping into anything.

[macdanger2]

A bit off topic but looking for some advice with re-hanging a curtain rail in a fairly old house. The plaster where it was up is very bad, crumbling away in parts and it came down a few weeks back. Am I best to just get decent-sized rawl plugs and locate it a few inches to the side if where it was?

Or should I get a length of timber and put it up above the window and put the curtain rail into that (I presume there's a name for that piece of wood)? The idea being that doing this will spread the load of the curtain rail / curtains

Thanks

[NP 76]

Probably better to put up the timber if the walls are old and flaking. It's called curtain rail and I'd 3 x1 clean timber. Put it on with hammer fixings and then fix the rail out through this

[Leonardo]

The length of timber is called Curtain Rail as well.
Might be better to buy Chemical Anchors though - depends how bad the wall is

[macdanger2]

Thanks lads