New Build - Drowning in Confusion

joefish1

Hello all,

I have a new build: house is storey and a half, three dorms to the upper front and rear and, to the lower front is two bay windows (with roofs) and a porch (with roof) - all 30-degrees - House is approx 2200 sq-foot - concrete build - hollowcore divide and concrete room partiitions upstairs also

The house is being roofed at present and triple glazed windows are being ordered. (.8 u value)

I am not using trickle vents or a heat recovery system, I want to get by with reasonably good insulation and I save turf therefore, main living room will have a pot belly stove with back boiler and ill burn solid fuel mostly and use oil as backup

So far the only measures i have taken is leaving a 6 inch cavity as opposed to four, I intend on pumping this cavity with bead, I have went for the best u-value window I could buy and they are triple glazed. I intend on using thermo board on the inner leaf of the house also. I also intend on using the tape around the windows upon installation. When the time comes ill be buying a high efficiency boiler and putting thermostats in the rooms

I have been hearing about breathable roof felt but as I say the roofing is about to begin with ordinary felt, is it correct to assume I dont need breathable felt if im not using a Heat recovery system

I have learned the part L of the new building regs mean i have to basically up my game on insulation and get a ber cert at some stage, Im now confused as to what i should do with the following (insulation wise)

- Dorms x 6 - all will have their own ceiling and roof
- Two Bays and Porch - all will have their own ceiling and roof
- Conservatory - This room will not have a ceiling but the ceiling will be at same angle as roof
- Floors - I am not going underfloor heating - What kind of underfloor insulation are people putting in these day
- Floors upstairs - I put in hollowcore - what would you advise insulation wise for upstairs - again no underfloor heating

Any advice is much appreciated

.... A Confused Joefish

BryanF

• stop roofing and immediately an go employ an air-tightness tester/arch specifier to correct your details so you don't have drafts for the rest of the buildings existence

• your having 4inch holes in each room, and worrying about insulation? get a BER assessor (preferably one that is also an arch) ASAP to check compliance with the TGD L - there is more to it than just insulation

• breathable roofing felt has nothing to do HRV? it dictates the type of roofing build up you install. who is your architect or supervising engineer? your roofing and this hasn't been decided?

none of what you ask can be answered without first doing a BER assessment to see what the minimum U-values for these elements you require are...

sydthebeat

joefish1 wrote: »

I have learned the part L of the new building regs mean i have to basically up my game on insulation and get a ber cert at some stage, Im now confused as to what i should do with the following (insulation wise)

- Dorms x 6 - all will have their own ceiling and roof
- Two Bays and Porch - all will have their own ceiling and roof
- Conservatory - This room will not have a ceiling but the ceiling will be at same angle as roof
- Floors - I am not going underfloor heating - What kind of underfloor insulation are people putting in these day
- Floors upstairs - I put in hollowcore - what would you advise insulation wise for upstairs - again no underfloor heating

you need to run the measurements and specification through the DEAP software to find out what you need to do to comply with minimum regulations.
When you do this you can play around with u values for these different elements youve listed above, before finalising the preferred u value based on cost versus performance.

It would be irresponsible for anyone here to try to suggest specifications for different elements without knowing if those specifications would meet regulations.

Regarding the ground floor, there is a minimum u value to be met and its directly related to the exposed perimeter of the floor, ie the more corners on the plan, the more insulation needed to comply.

On the first floor, if theres no UFH personally i wouldnt incorporate insulation. The floor slab will warm up regardless.

sydthebeat

merging with existing thread

No6

Do you have any professional supervising your build??, They should be able to advise you, if not hire a BER assessor who is also an Achitectural Technologist, Architect or Engineer, you sound like you are about to make a whole load of mistakes that will cost you lots in the long run in wasted energy costs, never mind not being in compliance with the building regs!!

joefish1

No6 wrote: »

you sound like you are about to make a whole load of mistakes that will cost you lots in the long run in wasted energy costs,

Not being confrontational but what mistakes do you mean

My architect is not well at the moment so unfortunately i cant approach him with these questions

thanks for the replies so far folks, i rang a local BER/energy consultant there an hour ago, im bringing the plans into him tomorrow and we are going to sit down tomorrow for an hour and come up with a complete plan on my insulation needs, as i explained to him im not aiming for a passive house, i dont believe in Heat Recovery Systems and im not aiming for an A-rated house but i do want a pratical and good level of insulation - im conscious that kerosene is going to go sky high but its still my humble opinion that if it reached 20-euro a litre i still wouldnt install a heat recovery system

sydthebeat

joefish1 wrote: »

im not aiming for an A-rated house

interestingly, minimum building regulations revised in 2011 would mean you'd have to build A rated.

you may have come under requirements to build under the old 2008 regs... but why not build to current minimum standard?

joefish1

sydthebeat wrote: »

interestingly, minimum building regulations revised in 2011 would mean you'd have to build A rated.

you may have come under requirements to build under the old 2008 regs... but why not build to current minimum standard?

Initially I though you only needed a BER cert if you built to sell or rent but now I hear it applies to me because its a new build so i said fair enough

I got planning permission in feb 2011 so if the rules say a-rated then i suppose thats what ill have to aim for, i was under the impression minimum level allowable was c1 standard - who knows depending on what this BER consultant chap says and what we agree on tomorrow i might do better than what i imagined he will lay out the plan and standards and i think ill stick to that - if you go researching insullation on the net you end up with a pain in your heat and everyone having different theories

Im aiming to do the best i can - im building the house to live in for a long long time hopefully, im not skimping - the only thing i banned outright was the heat recovery system and im not for turning on it but everything else i want to do to a good standard

personally from research the word room-vent is near taboo but im not using HRV so my only options are vent or trickle vent - both these have their pros and cons i see

BryanF

joefish1 wrote: »

from research the word room-vent is near taboo but im not using HRV so my only options are vent or trickle vent - both these have their pros and cons i see

they are not your only options. if your not keen on heat recovery ventilation what about demand control ventilation/positive input ventilation. you have the wall vents anyway and you'll have the extracts in kitchen and wc anyway so the rest of this type of kit is merely a central positive input unit that ensures your home gets adequate fresh air for your health and the buildings.

joefish1

BryanF wrote: »

they are not your only options. if your not keen on heat recovery ventilation what about demand control ventilation/positive input ventilation. you have the wall vents anyway and you'll have the extracts in kitchen and wc anyway so the rest of this type of kit is merely a central positive input unit that ensures your home gets adequate fresh air for your health and the buildings.

hmmm never knew such a thing existed and im liking what im seeing on sites so far.. thanks :pac:

BryanF

joefish1 wrote: »

hmmm never knew such a thing existed and im liking what im seeing on sites so far.. thanks :pac:

who will be certifying the stage payments if its your architect, you need to discuss with him and your BER assessor what is required to comply with the air-tightness, thermal bridging and renewable requirement, you may also want to consider removing the conservatory from the heated insulated envolpe unless you your willing to go with high spec glazing

joefish1

BryanF wrote: »

who will be certifying the stage payments if its your architect, you need to discuss with him and your BER assessor what is required to comply with the air-tightness, thermal bridging and renewable requirement, you may also want to consider removing the conservatory from the heated insulated envolpe unless you your willing to go with high spec glazing

Hi Bryan

Ive drawn down stage 3 of the 5 part payments - my architect is certifying them and is very very old school as in pencil and t-square level but then again he hasnt had a house fall on him yet

This chap im meeting tomorrow is a busy BER assessor and energy consultant so ill be leaving his office with the grand plan - im guessing he will cover air-tightness, thermal bridging and renewable requirement

How do i remove the conservatory from the envelope thing - the conservatory isnt the typical one, it more of a bright sun room - its concrete built with six windows and french doors. It will have the cavity pumped too, it wont have velux above but i dont want to put a ceiling in it but rather keep the angle of the roof on show

BryanF

joefish1 wrote: »

Hi Bryan

Ive drawn down stage 3 of the 5 part payments - my architect is certifying them and is very very old school as in pencil and t-square level but then again he hasnt had a house fall on him yet

This chap im meeting tomorrow is a busy BER assessor and energy consultant so ill be leaving his office with the grand plan - im guessing he will cover air-tightness, thermal bridging and renewable requirement

How do i remove the conservatory from the envelope thing - the conservatory isnt the typical one, it more of a bright sun room - its concrete built with six windows and french doors. It will have the cavity pumped too, it wont have velux above but i dont want to put a ceiling in it but rather keep the angle of the roof on show

as your glazing % increases so does its required U-value - your BER consultant may be able to help there.. sick architect, pencil and tsquare Jasus!

joefish1

haha He might be pencil and t-square but he designs a solid house and seems to know what the county council wanted. He is an old school architect he never led me to believe he was an energy consultant - the blocks have been done by a top class blocklayer and i have the pick of quality workmen on the site so that angle is covered - the only bit im dubious about is the insulation

Ill give you an example of some theries of my own, i seen a local cornmill which was tossed to make way for a lovely apartment block right on the river edge, the corn mill designed by the "simple men" stood operational for hundreds of years yet the apartment block which was designed by the men with the CAD and all the bells and whistles is now condemned and was never deemed habitable - now that could have been due to several reasons but although im glad advances have came along im not convinced that the brains of today are any better than the brain-power of yonder

As ive said im not going to be cutting corners ive a large cavity, using thermo-board for the inner leaves, taping the windows, high efficiency boiler, stats, .8 u value windows, back boilers etc etc but im the kinda chap who grew up with no rads in my homeplace, ordinary room vents and timber windows which before they were replaced you could see ice inside them on cold mornings and to my recollection i didnt suffer from constant flu nor did i develop asthma and the likes