self build

stevie200621

heya !! to all u people out there who have constructed your own house !! i am about to start buildin my own house so all advice on different aspects of it would be grateful !! from what insulation would recommend to type of windows etc !! its always afterwards ud see the things u would have liked to do different !!

muffler

You have come to the right place. There are loads of threads here in the C & P forum and dont forget to look at the sub forums also.

If you have any specific questions fire them up.

stevie200621

ok my first question is when buildin which will be better in the long run and guaranteed to last .... pump 6 inch cavity wit beads or put kingspan in the walls and kingspan insulated slab on inner leaf ??

sinnerboy

The insulation boards you refer to depend on Pentane gas which is trapped when the foam is blown to make cavity boards and the backing to insulated plasterboards.

But this gas does not remain trapped forever it leaks away over the years and a 25 year old board will insulate a lot less well than a new board.

Polystyrene insulations are stable i.e. they do not rely on trapped gas and maintain the same insulation value for decades.

I would think 200mm cavity minimum - and for that reason alone you will need a structural engineer.

Before you do anything else have you design assessed by a BER assessor NOW.


Your biggest challenge will be to meet Part L Conservation of Energy Regulations. Insulation. Air Tightness. Renewable Energy. Use these phrases to search this forum to appreciate why.

just do it

Good luck with the new build Stevie. Loads to read on here of value. The live self-builds thread is of great value - a few quiet hours reading there.

The one thing you'll come to realise is often there is no clear cut right answer. Each house and person has different needs, wants and desires.

badgerhowlin

sinnerboy wrote: »

Before you do anything else have you design assessed by a BER assessor NOW.

I would agree with this 110%.

I did\doing a selfbuild and did not know i needed to get a BER cert done so i only got one once everything was done. Luckly for me i had done everything right by the way of insulation and air tightness and i received a good A3 rating.

He told me if he was involved with the project from day one I would of more than likely have got an A2

So get a BER assesor

john_cappa

sinnerboy wrote: »

Before you do anything else have you design assessed by a BER assessor NOW.

By design you mean the house plans yes?

Engaging with a BER at this stage allows you to build the specification (what wall insulation, roof, floor insulation, heating system, windows etc??) to achieve a certain rating is it?

stevie200621

Is it necessary to get this cert thou if I'm goin to be livin in the house and never intend sellin or Rentin !? Who will be Lookin for it ??

sydthebeat

stevie200621 wrote: »

Is it necessary to get this cert thou if I'm goin to be livin in the house and never intend sellin or Rentin !? Who will be Lookin for it ??

yes it is necessary.

not only is it legally required but the process of checking that your build is building regulation compliant is practically the same... so you need to get it done regardless.

a BER certificate is required for any house for sale, for rent, or newly built.

just do it

stevie200621 wrote: »

Is it necessary to get this cert thou if I'm goin to be livin in the house and never intend sellin or Rentin !? Who will be Lookin for it ??

Despite the fact that it is necessary, it is potentially the best money you'll spend.

One final tip, get a professional to design the build of your house, not the builder. Designer to design, builder to build. The designer, such as an energy assessor or architectural technician, should also be able to do the BER for you.

If requesting references on here make sure to do it by PM.

sinnerboy

stevie200621 wrote: »

Is it necessary to get this cert thou if I'm goin to be livin in the house and never intend sellin or Rentin !? Who will be Lookin for it ??

Stevie the BER assessor can advise you on options before you dig a hole in the ground. Nothing at all to do with the BER Cert.

What level of insulation / air tightness/ double or triple glazing / heat pump or boiler ? / solar panels / natural ventilation or heat recovery ... and so on. The software that the assessor uses can inform your decisions. You can ask to see the affect of various combinations of build options. A lot more than "spitting out a cert" is available.

As much as you possibly can aim to make make EVERY decision on the build before you start. Plan for 2 years build for 1 year enjoy for 25+ years.

fclauson

sinnerboy wrote: »

The insulation boards you refer to depend on Pentane gas which is trapped when the foam is blown to make cavity boards and the backing to insulated plasterboards.

But this gas does not remain trapped forever it leaks away over the years and a 25 year old board will insulate a lot less well than a new board.

Polystyrene insulations are stable i.e. they do not rely on trapped gas and maintain the same insulation value for decades.

I would think 200mm cavity minimum - and for that reason alone you will need a structural engineer.

Before you do anything else have you design assessed by a BER assessor NOW.


Your biggest challenge will be to meet Part L Conservation of Energy Regulations. Insulation. Air Tightness. Renewable Energy. Use these phrases to search this forum to appreciate why.

Make sure you look at the 90/90 value for U-value (now required in UK BBA certs and I think in the NSAI ones)

there were cases of boards being tested direct out of the press - this is now not the case and the 90/90 value is used

stevie200621

thanks for replys there !!! does anybody know anything about piling, ring beams methods ?? gettin piling done soon and was wonderin how floor will work afterwards !!

BryanF

stevie200621 wrote: »

thanks for replys there !!! does anybody know anything about piling, ring beams methods ?? gettin piling done soon and was wonderin how floor will work afterwards !!

I presume this is for site reasons - it can be a great way to reduce your concrete consumption -low CO2 and all that:).. you can pour, get pre-cast or use timber beams but that's about all the info I should offer because you NEED to talk to YOUR structural engineer;) best of luck

you could also have a chat with a M&E /piling specialist as there is scope to insert geo heat pump technology as part of the piling process - it may be expensive though but worth the discussion

stevie200621

BryanF wrote: »

I presume this is for site reasons - it can be a great way to reduce your concrete consumption -low CO2 and all that:).. you can pour, get pre-cast or use timber beams but that's about all the info I should offer because you NEED to talk to YOUR structural engineer;) best of luck

you could also have a chat with a M&E /piling specialist as there is scope to insert geo heat pump technology as part of the piling process - it may be expensive though but worth the discussion

thanks bryan ! ya know theses structral engineers thou go overboard ha !! i have the piling part sorted and then the ring beam goes around on them ! i think ill either have to put precast concrete slabs onto these then or pour a kinda raft foundation on these too which is gonna be very costly !!

muffler

stevie, just in case you wander down the road of asking anything about raft design etc could I ask you to have a quick read at the forum charter. Thats our bible so to speak and it will only take a minute or two to read.

It just outlines what can and cant be discussed etc.

brdboard

stevie200621 wrote: »

thanks for replys there !!! does anybody know anything about piling, ring beams methods ?? gettin piling done soon and was wonderin how floor will work afterwards !!

Stevie,

Speaking as a structural engineer, you really should have a good idea of what you are doing with your foundations( ie ring beam) and floor slabs before you start piling. It's not a matter of piling, then figuring out your beam layout, then thinking how your slab is going to work.
The location of load bearing walls will lead to the location of beams which in turn will decide your pile locations, so piling without thinking this through is going about it backwards.

BryanF

brdboard wrote: »

Stevie,

Speaking as a structural engineer, you really should have a good idea of what you are doing with your foundations( ie ring beam) and floor slabs before you start piling. It's not a matter of piling, then figuring out your beam layout, then thinking how your slab is going to work.
The location of load bearing walls will lead to the location of beams which in turn will decide your pile locations, so piling without thinking this through is going about it backwards.

Brdboard, could you give us your views on the use of timber ring beams/ construction post piling, instead concrete. presuming domestic spans wont be crazy big.. lets assume the client is eco motivated. what are the issues/pro & cons to using timber thanks. I appreciate there are huge variables:)