New Build... Advice please !!

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kojak

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Hi all,
Myself and my newly married wife are at the planning stages of building our own house (plans sent in now waiting to hear back).
Anyway we have a couple of queries, some probably more important over the others.
1) We are building a 3200sq ft house on my wifes family land (approx 1 acre), we are so confused as to which heating system to put in, we propose to have UFH downstairs and also upstairs using a hollowcore floor, our brains are about to run out of steam if we cant decide on which system to go with.

We were originally thinking of going with geothermal because of the house size, but then we have heard alot of horror stories about huge electricity bills, then we were thinking of going with a good quality solar panel system and an oil condensing boiler but would this be sufficient for our house size and needs and again what kind of expense would this be to run and install ? Pellet system was another option but maintenance and pellet storage was a worry, also looking at the air to water system (which we dont know too much about)
Does ANYONE have any experiences or advice for us on this ??
VERY CONFUSING but want to make the right choice....:confused:

Secondly,
INSULATION....
Now i know the key to a warm house is insulation, we were thinking of putting 60mm kingspan in between the cavitiys and then installing warmboard (or insulated slab boards) on the inside, would this be the way to go to achieve a warm A rated house ? Also our windows and doors will be (if budget allows) triple glazed to try and achieve this, if not then a very good double glazed.
If anyone has any other ways of doing it or if they think this is the best way i would gladly like to hear, because we want to do things right from the start and not be sorry later, also bearing in mind the budget :eek:
Also should i use kingspan to insulate between rafters or is there anything better to use keeping in mind the costs ?
Any information on insulation (or anything at all for that matter) would be greatly welcomed :)

Thank you kindly in advance.
 
Hi Kojak,

I've been reading these forums for about 2months now & I have decided to register & this is my 1st post.

I am in the early stages of planning for my own house at the moment....

I am an architectural technician myself & here's what I am doin in my house (2700sq ft)...i'll try keep it short

1)Solar tubes system (alot better than solar panels in my opinion) and an oil condensing boiler & ufh

i am not convinced with the geothermal systems (I think they will improve greatly over the next few years)
& I am not overly convinced on the wood pellet stoves either

2) It amazes me how many people use kingspan I would use a different company (not sure if I can give details here?) as its everybit as good (if not better) & it is cheaper.
I am using 80mm in the cavity & 40 insulated slab internally.
As for windows I would recommend using treble glazed windows, it's only a matter of time before it becomes a regulation that all new dwellings will have to have triple glazed windows (it's what they do in Germany)...
I know of a company that I would highly recommend, they are fair superior to any other in this country both in cost & quality.


Also, if I were you I would look into rain water harvesting, as we will be charged for usage of water shortly & I think it's only a matter of time before people who have they're own wells (which I hope to have) will get charged too.

You could just have all rain water piped to 1 manhole so if we do have to pay the water charge, it would be very easy hook up your rain water to a harvesting tank


& If you want details on the companies I woud reccommend for solar tubes, insulation & windows pm me.

Hope this post was of some help to you!
 
Cheers bravojohnny,

Great post,
pm sent to you by the way regarding names and numbers, thanks for that.

That's some interesting information there, especially the point on rain water harvesting will defo look into that a bit more.

On the solar panels... i have heard that the tubes wont last as long as the panels and are easier to break meaning more maintenance etc, do you know much else about them ?
Also with the panels and oil condensing burner, do you know what the running costs are on this approx ?? opposed to the geothermal electricity bills.

Great post,Thanks again
 
Kojack,

Without creating an ONQ style thesis :p I will try and give you some pointers & guidance on this.

As you are starting a new build you have a blank canvas.

My recommendation is to forget the traditional methods of building and think out side of the box.

You have the ideal opportunity to build a home that is not reliant on geothermal heating or solar tubes or any other form of renewable heat source which is in the main never going to achieve breakeven on its costs. In many cases a solar heat collection system designed to suit a house adequately will be so expensive in upfront costs that it can take 80 years of savings to recover the cost of installing it!

You would be better served by considering a high level of insulated home, bordering on achieving Passiv House standards. Passive House is expensive to achieve and a compromise is to work towards the standard ratehr than trying to achieve them.

A clever design team will work with your site, aspect, attitude (of site) local conditions and work out a house plan that will make the most of encouraging solar gain and heat storage through thermally massive internal structures ( walls and floors). They will then strive to minimise heat loss through insulation levels, high airtightness control, controlled ventilation and the actual structure of the house itself.

These design ideals will also help keep the house cooler and temperature controlled in the brief periods of summer that we get.

If you build clever you will minimise the amount of heating required and will only need a heat source for comfort or back up in depths of winter. This can be a solid fuel / wood pellet back boiler system which will do radiators / UFH and hot water.

A gas or oil combi boiler may be perfect for your hot water usage so you are not storing hot water for reheating continuously. You could use a small solar tube array to supplement this hot water production in a closed system.

The actual design of your heating system will come down to your current usage patterns and also with the expected long term patterns as a single person or couple have different requirements to a family etc.

Best of luck.

Sean
[broken link removed]
 
+1 what Sconhome said.



[broken link removed]

ONQ.

(taking a break from writing theses)
 
Kojak, we are in our house just under two years now, and also went through trying to decide between ufh, geothermal, wood pellets, in the end we decided against geothermal because of the esb costs you mention and against wood pellet because of someone we knew who got one ( a 'good' one - he's a plumber himself) and was so disappointed with it he ripped it out after 2 months and put in an aga. We went for a Rayburn in the end, expensive ( about 7k) but would not be without it, it's extremely efficient on oil (1 tank each of the last two winters) , heats the hot water as well and of course, cooks. You can have either the cooker or the heating on separately or together, if you are just cooking and don't have the heating on your kitchen will still be warm ( although themes ones don't give out as much radiant heat as the old ones used to cos they're more efficient)

plus it looks fantastic, no boiler outside to go rusty and ruin your view when on the patio. I love mine. I wanted to do the eco thing but just felt the right answer wasn't out there yet and as the Rayburn is so efficient I think we're doing the best we could.

Btw they're all programmable now with timers etc.

We don't have ufh but surely that would be very expensive with an oil boiler as ufh needs to be on the whole time doesn't it?
 
onq said:
Did you not see the exchange between DBK100 and me about the new act? http://www.askaboutmoney.com/showthread.php?t=132234 Its the The Land and Conveyancing Law Reform Act 2009. Great for small builders, not so good for rose-growers. But watch out for those demolitions. :) ONQ.
Click to expand...

Been following it. Had to let you folks tease it all out to see how well you understood the legislation before I'd comment!

Sure if you'd asked me I could have told you in England there was a rule that you own and maintain the wall on the left of you property, cuts out neighbourly disputes.

Any plant growth trespassing over the party line can be cut back to the mid line and you must return the property to the neighbour!

I had a very irate new client recently who was very upset when I informed them that they were not planning exempt as they had to demolish the existing kitchen return to allow the 40msq extension to go ahead. Needless to say the comment "all the other builders said we were exempted development" required written notice of the ruling to reinforce my point.

We are now going forward as a design & build team.

My next targetted specialisation is to produce a condensed form of your posts, like exam notes!! :D
 
I would echo Bravojohnny's points - though I personally think that the Aeroboard 140mm platinum board is a better product than the thinner PIR insulations - as there are fewer gaps and less chance of thermal looping.

Focus on a good southerly aspect, preventing draughts and lots of insulation in that order - and just go for a simple oil boiler.

Also flat panel solar panels are more fool proof than the vacuum tube.

Do at least consider going for a good quality timber frame house too - build quality for insulation is generally better and one can engineer out sound problems.

Regarding your roof, depending on whether you have a dormer or not, putting in loads of fibre glass (400-500mm) is likely to be the cheapest option.
One thing I would also recommend is to think of bits of your house in terms of how easy it would be to upgrade that element:
so it is generally simple to replace a boiler, easy to add roof insulation, ok to replace windows and a real pain to reinsulate your floor. If you are going to compromise in terms of insulation - think of that.
 
Right - back to the theses.

Normally I'd agree,with you Superman, but adding 400-500 mm of quilted roof insulation may not be the answer.
Quite apart from anything else, it will tend to totally block the eaves insulation minimum 50mm air gap and cover services.
Any quilted insulation at first floor ceiling will be unworkable in terms of vapour checks if there are downlighters or badly fitted vents.

Deep insulation if this order really requires the services to be routed at high level to avoid damaging them and creates hazard underfoot.
Its one thing to have 150mm quilt between the 150mm joists, but with deep insulation you can't see where to place your feet in the attic.
Worse, if the services are above the level for safety they run a higher risk of freezing in the winter, which means this needs to be re-thought.

More than once I've seen 300mm of insulation stuffed into a space 150mm deep, the installer thinking they'll get the benefit of a 300mm insulation layer.
Quilted insulation 300mm deep must be installed to its uncompressed depth to work as designed, which is to trap a 300mm deep layer of air.
It works by preventing this air circulating, creating a composite material of air and glass fibres that doesn't transmit heat well.
I have seen insulation stuffed in to tightly that it had no chance of working as intended - nearly "solid" in fact..
If you don't provide 300-400mm depth to install it, don't install it and crush it - that's just money wasted.

In my opinion its far better to install HD boards following the line of the roof - and don't crush them either! :)
I would strongly suggest doing the hard work and installing these between the sloping roof rafters, leaving the 50mm gap behind venting eaves and ridge.
This is more difficult to do, and in particular to do well, but it means that the entire attic is kept warm, significantly reducing concerns about freezing pipes in the winter.
You do have to think more carefully about service routes and bathroom ventilation, but that will probably need to be routed via the Mechanical Ventilation and Heat Recover system these days.

You can come along later and install a plaster finish and vapour check to more HD insulation boards to the face of the joists, building up a really good level of insulation and air tightness.
With sealed breather paper to the outside of the joists, the house will be wind tight, but not vapour tight - it can breath but you won't be blown out if it.
There are several firms offering building systems which will do all of this, and you should take advice from your architect in relation to this work and the benefits of it.
You should install upgraded highest floor joists at this time - the increased material costs will be minimal and will pave the way for a future attic conversion.
This is yet another reason to install insulation following the line of the roof, it means the work of insulating the attic level is done once.

Here are the regulations you must build to by law
http://www.environ.ie/en/TGD/

Here is the new Part F
http://www.environ.ie/en/Publications/DevelopmentandHousing/BuildingStandards/FileDownLoad,1647,en.pdf
See Diagram 11 "Ventilating Roof Voids" , Section D "Ceiling Following Pitch of Roof" P. 28

Can I also suggest you look around AAM for helpful articles, both here and in the Homes and Gardens forum and also the askaboutlaw forum.

Can I also respectfully suggest you take a scan over the Self-Build FAQ in case there is information there which might help your endeavour.

http://www.askaboutmoney.com/showthread.php?t=126261

ONQ.

[broken link removed]

All advice on AAM is remote from the situation and cannot be relied upon as a defence or support - in and of itself - should legal action be taken.
Competent legal and building professionals should be asked to advise in Real Life with rights to inspect and issue reports on the matters at hand.
 
I always enjoy reading ONQ's posts, they're very informative.

I'll just get back to a few tings kojack asked.
(I am open to correction on the below comments)

From what I know of solar panels they are not as suited to our climate / environment (overcast / cloudy / not much sun) as much the tubes are.
Also, if a panel is damaged you have to replace the whole thing which is costly, time consuming & while you are waiting to get them replaced you have no solar heating.
Now if a solar tube gets damaged you only pay for the damaged one/s, which is cheaper, easier to install & you still have solar heating as the other tubes are working.

You might ask how would solar panels / tubes become damaged. Wind for one thing can be a factor & from what I've heard the panels are less resistant, due to their larger area.

While we are on the subject of solar heating, as far as I'm aware grants(approx. 800e?) are not available for using them in new builds. However you are entitled to apply for the grant for installing the systems if you are living in you're 'new' house for @ least 1 year.

So you can make all the necassary steps for installing the systems at a future date now while you are building, which will make it easier install at later down the line. eg pipework etc..

Just a quick note on internal insulated slabs:
It's alot easier for a plasterer to plaster an area of insulated slab than blockwork. So you should be able to get a plasterer to lower the price beacuse of this. It more than likely won't be a massive saving, but it's better than noting.

Once again I am open to correction on any of the above & I do apologise if I have given any incorrect information.
 
bravojohnny,

How does wind damage solar panels?

Is this by wind-blown debris or vibration due to them being inadequately fixed?

ONQ.
 
Hi ONQ,

Sorry I should have explained that, wind damages panels / tubes just like you said.

Just like high winds can damage slates / tiles / ridge tiles, chimneys etc.

I know it's not an every day occurrence, but it's something to bear in mind.

I hope that answers your question.
 
Okay it seems to hinge on how well its secured.

One thing that causes me concern is the installations that seem to rest on four "stalks" coming up out of the slates, presumably suported off an existing rafter.

These stalks generate point loads, with variable wind loading, so I'd be concerned that joists might not be adequate to support them.

Normally when you inpost point loads in a timber joist membrane like a floor or roof, its to put a hole in it for a stairs, velux or dormer window.

The Trimming/Trimmer/Trimmed arrangements of joists is installed with the Trimming joist sometimes doubled to assist with load transference back to a supporting structure.

People seem to be just bolting on either tubes or panels to existing roof joists and I'd appreciate a comment from any engineers reading this about whether that is good enough.

ONQ.
 
As someone who is just completing a 3000 sq ft bungalow (what was i thinking???) I would knock at least 500 but probably 1000 sq ft off my own build if i could go back again.

I see you mention the word budget in your post so its obviously on your mind - my advice would be to go smaller and do it right rather than big and trying to save money. If this means re-submitting plans and an extra couple of months waiting then so be it. You'll be there for a lot longer than a couple of months...

One other thing would be to keep the roof simple. (probably too late if plans are gone in). Its one area where complicated sections can cost a lot extra. Plastering, blockwork, kitchen, windows electrical, carpenry etc. all increase relatively in proportion to the size so decreasing by 20% would approx decrease the costs by 20%(may be some economies of scale here but 1000 blocks cost more than 800 blocks at the end of the day)

My build cost me approx 120 sqft to get finished excluding painting/furniture/landscaping/entrance etc. so for your build (taking an estimate of 120 sq ft to get in with PVC windows, 8k kitchen, trutone slates) at the moment you would be looking at 384k

Then you have painting (7k), landscaping (??? whatever you want to spend), driveway(5k), blinds(3k), furniture(how long is piece of string but your talking at leat 10k for table/chairs, couches, 4 bedrooms), flooring (laminate - 10-20sq/yd) Tiling - 50/60 sq/yd), architect fee, council, entrance gate/walls (5k)

You may be able to do better. Complicated roof cost me about 20k, being a bungalow prob added another 20k so this would bring it to 105 sq/ft

You may not want to read this but if i could go back i would re-submit revised plans for a smaller house with the possibility to build on in future. I know when i was at planning stage all i wanted to do was get started but for the sake of a couple of months re-applying i would have saved myself a lot of financial worry and got a better finish to my house.

Do i really need a large kitchen/dining area or a guest room and spare room or could i have knocked 500 sq ft off and had 55k in my pocket.
 
sorry ... i havent really answered your qs in my previous post. more of a pesonal lament brought about by a 400k bout of buyers remorse....

I would speak to a builder or QS even informally at this stage and see what they estimate it might cost. The planners might not have looked at your drawings yet and may accept and additional revised drawing (???? dont know if this is possible).

I gave my architect a budget figure of 350k (which included contingency of 30k) to get us in, landscaped, furnished, everything and here i am 360 spent and another at least 50 to go. and the best part is - we decreased the size of his original drawings from 3600 to 3000 before going for planning. I feel really let down that he did this and angry with myself for letting it happen.

If you have costed everything out and can afford that size house then work away but dont make the same mistake i did. Do you have an architect on board to help with these heating decisions? He should be able to advise on the most suitable system for you
 
Sman,

that a scary figure, could please give a bit more detail?
1) did you use a main contractor or self build?
2) Geothermal or oil fired
3) Location - Dublin I hope?
4) Are you including the price of the site
5) Natural Stone?
6) Double or trebled windows
7) Garage ?

I plan to self-build a 3000sqft + garage with UFH oil fired, some natural stone, free site, double glazed, highly insulated house for €220,000 and that includes a €20k contingency!
 
House,

Interested in those figures as hopefully going to get a contractor to do a build on a family site in Dublin. PP has not gone in yet but Architect gave a figure of 220k before VAT which include 20k for siteworks / rainwater harvesting and disposal for a 1500 ft2 house. Works out at €130 per square foot. Cheers.
 
1) did you use a main contractor or self build? Project manager. fee approx 30k. again possibly a mistake as he said he would do it for 300 but didnt work out like that. My fault to beliwve the arch and PM and go into it with an attitude that it would cost what it costs
2) Geothermal or oil fired - Oil with U/F throughout. Geo was 10k extra
3) Location - Dublin I hope? South East
4) Are you including the price of the site. Free site
5) Natural Stone? About 90 sq mtrs - cost 8k overall. 3 for stone and 5 for laying (again a luxory i could have done without even though we got a good deal on it)
6) Double or trebled windows - double PVC
7) Garage ? Yes. too big. In hindsight would have left it and got one of those galvanised sheds and screen it with trees. Garage prob cost 15k

You would be doing very well to do it for 220.
I didnt go overboard on anything really. no bells and whistles. and plenty of bargaining for everything.
If you did it yourself you could save the 30k and build a 2 story (-20k), simple roof design (-20) but your still up around the 105-110 though.

A friend of mine recently completed a standard dormer build approx 2500 sq ft (standard insulation, ventilation etc.) and it cost him 130 all in. including basic garden, furniture to get in etc.
If you can do a lot of the work yourself then you might be able to do it for 220 but i would think it is impossible to build that big for that amount.
I would advise speaking to an experienced architect and explain your budgetary restraints and emphasise that you can NOT go over on that amount and he should be able to advise on what size/spec you can expect. (dont tell him about the extra 20k though) keep that as your own contingency :)
 
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