Tue, 19 Dec 2023 05:47:47 +0000 http://www.greenbuildingforum.co.uk/newforum/ Lussumo Vanilla 1.0.3 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=6274 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=6274 Tue, 14 Sep 2010 06:55:41 +0100 stephendv http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=6041 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=6041 Sun, 18 Jul 2010 20:36:27 +0100 stephendv Base and wall detail: http://www.casanogaldelasbrujas.com/base_and_walls.jpeg
Roof detail: http://www.casanogaldelasbrujas.com/roof.jpg

Foundations will be 10 pillars which support a glulam base 200x320 and normal timber floor trusses 40x160. I've been pouring over american house building books so am not sure of the European or metric standard sizes for the twobaX's they keep mentioning. So a few questions:

- Instead of using OSB between floor trusses to hold the insulation in place, can I use EPS panels instead - two birds one stone?
- What are the standard sizes for truss hangers?
- According to american code 40x100 studs (2x4) have to be at 400mm centres - could I go to 600 for such a small building?
- To simplify the roof trusses, I plan to build the front wall higher than the rest, then join the ceiling rafters directly to the studs in the front wall, is this ok? Will I need blocking in the front wall or will the interior OSB sheathing be enough?
- Roofing will be 4m long metal panels, do I need any kind of moisture barrier underneath it? If so, can I lay the moisture barrier directly on the rafters?

Thoughts welcome]]> http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=6237 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=6237 Sun, 05 Sep 2010 12:12:27 +0100 stephendv
The foundation is done for our timber frame cabin in northern Spain and I'm wondering about all the different cladding options available. Most of the literature I've found on the internet is written for wetter climates and describes things like "driving rain" which doesn't happen here. We have thunderstorms or slow rain over a few days followed by dry weather.
Summer is very dry reaching into the high 30's. My biggest concern is degradation through UV, so was hoping to draw on the expertise here for some advice as to which type of wood to use for cladding and which (if any) coating to apply...
Would like to preserve the natural look of the wood so a completely opaque coating is out of the question. The thermally treated claddings like thermowood seem to be good value compared to more expensive woods, but does the thermal treatment really help in a dry climate?
Which coatings/treatment do you recommend?]]> http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=5961 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=5961 Mon, 28 Jun 2010 08:31:56 +0100 stephendv 1. EPS backed plasterboard (EPS because it's easy to cut out service channels) 90mm total, 70mm EPS
2. OSB taped for airtightness
3. 89mm stud filled with rockwool
4. Breather membrane, preferably metalic to keep the house cooler in summer
5. 25mm diagonal battons for ventilation gap
6. Vertical wood cladding (thermowood)

Gives total u-value of 0.26.

Reason I put the EPS on the inside is to leave a vapour path open on the outside - is this correct? Is it OK to have the stud exposed to the air cavity?
The majority of kitchen appliances will be on an inside stud so the only real "services" in the whole house will be a few wall plugs, lights and light switches. Should be doable by cutting into the EPS and using plastic channelling - is PUR also easily cut this way?

Is there a better way to do this?]]> http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=5998 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=5998 Tue, 06 Jul 2010 23:48:48 +0100 stephendv Thinking of using a steel base with a conventional timber floor layer on top resting on 8 pillars. This would mean that the maximum span will be 3m length wise (4 pillars in 12m) and 4m across the width.

First layer is a steel frame UPN channel 160mm around the perimeter with 4 internal steel I-beams 120mm. 2 ibeams lengthwise and 2 widthwise.
On top of this a wooden floor layer composed of 50mm x 100mm beams and trusses. Beams lie directly on the steel perimeter u-beam. 4m trusses on 600mm centres are supported by the steel I-beams so that maximum span is 1.3m.

- I sort of plucked the steel dimensions out of the air, is anyone able to do a quick calc? If the house is ever moved the crane would lift it using 2 slings, so that would mean 4m spans.
- Are 50x100 (height) trusses on 600mm centres across a 1.3m span ok?
- Where the trusses rest on the 2 i-beams, does there need to be something in between? (rubber, glue?)

Some diagrams to hopefully clarify the ideas here: http://www.casanogaldelasbrujas.com/baseplans.jpg]]> http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=5813 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=5813 Sat, 15 May 2010 21:02:41 +0100 Justin
I could take all the old for recycling and buy new, or try to flatten and temper the old to make it workable.

Any experience/views/metalurgy on this?]]> http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=5804 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=5804 Wed, 12 May 2010 10:52:10 +0100 TheOldSchoolHouse
Are there any other considerations between the two that I ought to know about? Thoughts appreciated.]]> http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=5749 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=5749 Sat, 01 May 2010 14:56:56 +0100 tony
Should we measure this in KWh or £ or tonnes of carbon?

To me energy consumption should only be measured in kWh

I recently saw an interesting unit, W/K this a bit similar to degree days used for calculating fabric losses and I liked it but it is rarely used.

To measure in anything other than kW over a period of time turns it into a relative rather than an absolute measure.]]> http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=5441 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=5441 Wed, 03 Mar 2010 11:42:55 +0000 storm
Just perchance your beautiful Eco homes should be caused to tumble down upon your beautiful Eco heads ....

Rumour has it that the Haiti quake was no accident. That instead it was deliberately caused via sonic weaponry from the Haarp project brigade. ( Tell me something new 9 / 11 ! ). Now, as I had anticipated , there has been yet another quake, this time, in Chile. So, * just incase * , they point the beams your way. I thought I would enlighten you with a nifty little strategy of protection. :smile:

Check it out !

http://articles.mercola.com/sites/articles/archive/2010/02/25/how-to-survive-an-earthquake--tips-from-a-pro.aspx]]> http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=3013 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=3013 Tue, 25 Nov 2008 22:19:35 +0000 sinnerboy
Anybody can point me towards a system to provide copper clading over a timber framed wall and roof ( new build ) - providing for vapour diffusion ?]]> http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=5105 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=5105 Fri, 01 Jan 2010 02:02:05 +0000 tony
Hot box tests when applied to glazing do not take these into account as far as I can see.

Theses can be huge losses as radiation losses are proportional to the difference between the fourth powers of the two absolute temperatures and space is essentially at absolute zero the upper atmosphere to which some heat is radiated is very cold too over a hundred degrees below freezing!

Even the surface temperatures of flat roofs can fall way below zero indeed -30 C is common in the night during summer where air temperatures are much warmer, in winter this will be true but less noticeable.

Are radiation losses only something that we have to contend with in the real world but not in models?]]> http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=3999 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=3999 Mon, 11 May 2009 18:54:30 +0100 tony http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=5162 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=5162 Tue, 12 Jan 2010 09:35:04 +0000 tony
If I had £2000 to spend on renovations should I use it to improve my fabric insulation or to buy new windows with?

What are the returns like in either case?

Which is the greenest option?]]> http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=5137 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=5137 Thu, 07 Jan 2010 13:04:59 +0000 cha0s
The house is approx 1850's in parts. and those parts are the problem :-)
I think the bathroom wall is solid (no cavity) and it gets cold and has lots of condensation. esp around the window.
Is there anything i can do to minimise this?

There are vents above the window? will blocking these help?
We will be looking into external and internal insulation on the solid walls in the house. But need to assess what will happen about having to move windows etc so they are flush with the outside again (is this an issue?)

(btw the heating has just died in the last couple of days, and guess what, no condensation!)

The front door also has the same problem, its wood (pine probably), fairly thin. maybe 20mm?

any thoughts?? thanks.]]> http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=5040 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=5040 Wed, 16 Dec 2009 22:15:52 +0000 cha0s
Im going to add insulation to our loft.
How much air gap should I leave round the eaves.
How do i tell if i have breathable felt/whatever.
If i have the breathable stuff do i need an airgap?
If i need an airgap, is there some nifty (and cheap) plastic moulding i can use to maintain the gap?
And.. in one room we have sloping (slopeing?) ceilings on one side.. can i shove rock wool insulation down there, as the current pink foam boards dont seem to be doing much.

Also, i have it in my head that i need to insulate over the cavity, so cold air dosent get down there, I think there is cavity insulation (rock wool batons ??) but i bet cold air will still get between the insulation and the wall!
So do i need to do this?



Thanks.]]> http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=5039 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=5039 Wed, 16 Dec 2009 21:48:27 +0000 rippa701 I am starting on an eco-build and will be using straw bale walls clad in Heraklith board. The board manufacturer quotes a thermal resistance of 0.6 m2K/W. Can someone tell me what u value that is and how you get there?
Thanks]]> http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=4988 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=4988 Wed, 09 Dec 2009 17:58:49 +0000 39North
Sorry if this is not under the correct subject, but wasn't sure where to place it.]]> http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=2049 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=2049 Wed, 02 Jul 2008 13:21:22 +0100 greenman
A truly 'green' building must be one that is 'green' in terms of the extraction of raw materials, manufacturing processes, transport, energy consumed, impact on the environment, ecology, the energy efficiency and self-sufficiency of the resulting structure, its anticipated life expectancy, the ease with which materials could be recycled in that event, and so on...

Given all this (and the things I've missed out), but ignoring current fashions, aesthetic considerations and other peripheral matters, what is the 'greenest' building type (for a home), construction method, and combination of building materials there is?]]> http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=4218 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=4218 Wed, 01 Jul 2009 09:07:01 +0100 sinnerboy
http://www.boards.ie/vbulletin/showt...2#post60940702


EU - INSTITUTE FOR HEALTH AND CONSUMER PROTECTION Report No23
Ventilation, GoodIndoor Air Quality
and Rational Use of Energy

8.5.2 Mechanical ventilation
Buildings with mechanical ventilation have fan powered supply air to and exhaust air from the rooms. Supply air may be heated depending on demand but not humidified or cooled. Ventilation system may have heat recovery from exhaust air. System may recirculate also return air.Windows may be sealed or openable.These systems are common in countries with
moderate or cold climate where air conditioning is not always needed to maintain thermal comfort most part of the year.Technical details of these systems for good performance are described in a European draft standard (CEN,prEN 13779,2003).
Risks in the performance of mechanical ventilation include the following:HVAC-components may be dirty when installed or become dirty and release pollutants and odours;poor control of indoor temperature due to absence of cooling;low humidity in winter;noise generated by forced air flow and fans;draft caused by forced air flows.If the system has mechanical cooling the additional risk factors are introduced by cooing coils: condensed moisture in the system (e.g.cooling coils and drain pans) and potential microbial growth;biocides used to treat wet surfaces such as drain pans. In systems with air recirculation some additional risks are introduced:indoor-generated pollutants are spread throughout the section of building which
air handling system serves; higher air velocities which increase risk of draft and excessive noise; supply ducts of HVAC-system may become contaminated by indoor generated pollutants.

.........In mechanically ventilated buildings the ventilation air is conditioned before it is supplied to the rooms via the duct system.Because of supply and exhaust air fans the system is more flexible in respect of building design, and more energy efficient if heat recovery is used.
However, studies in many European countries have shown that mechanical ventilation systems may cause adverse heath effects,the reasons of which are not yet well known,but the following have been suspected:air handling system is a source of pollution,moisture in air handling system causes the mould growth, system generates and transfers noise, ventilation air supply is poorly controlled, occupants cannot influence the ventilation.
These issues have to be solved to achieve good indoor air quality.

http://www.inive.org/medias/ECA/ECA_Report23.pdf]]> http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=4556 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=4556 Mon, 14 Sep 2009 23:41:10 +0100 tony
It seems selfish to me to work things out over the short or medium term.]]> http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=2663 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=2663 Sat, 04 Oct 2008 15:29:58 +0100 tony
It as good as Passive haus standard? or better?

Can we put energy consumption numbers on it?]]> http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=4115 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=4115 Sun, 07 Jun 2009 12:52:10 +0100 tony http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=4116 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=4116 Sun, 07 Jun 2009 12:54:06 +0100 tony http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=3220 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=3220 Sun, 04 Jan 2009 18:11:48 +0000 tony
1. Cavity walls

2. Blob and dob

3. Aerated concrete

4 ? Too little insulation

5 not building air tightly

6. cement mortar

7. too deep foundations

8. uninsulated suspended floors

9. Roof trusses

Can you add any more]]> http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=3982 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=3982 Fri, 08 May 2009 10:55:13 +0100 tony
Everything insulates to a greater or lesser extent --- to imply that a material is thermally insulating there must be a minimum job that it does.

We need numbers -- I would say U values should be those numbers but that would always imply a specific thickness --]]> http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=3856 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=3856 Thu, 09 Apr 2009 19:31:01 +0100 tony http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=3673 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=3673 Sun, 01 Mar 2009 15:00:39 +0000 stephendv The ground floor is about 200m2 and so is the basement, simple rectangle. Is the thermal bridging between floor slab and exterior significant in a passivhaus build? If so, what are the alternatives to minimize this bridging without increasing the building costs considerably?
Tony has solved the problem by having a double basement wall with insulation in between. This looks ideal, but would mean much more concrete and higher costs. The house is in Spain, hence all the concrete and blockwork :)]]> http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=3234 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=3234 Tue, 06 Jan 2009 11:32:16 +0000 James Norton
1. List of common assessments
2. Summary of history / 'agenda' of the different assessments
3. Pros and cons of each
4. Relative costs of assessment
5. Software
6. etc etc ...

J]]> http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=3200 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=3200 Mon, 29 Dec 2008 14:52:52 +0000 tony
They do however use this power to extract heat from the surroundings -- this heat is largely solar energy.

The COP (coefficient of performance) generally 3 to 4 means that for each kW of energy put in you get 3 or 4 kW of heat energy out.

This is reason that heat pumps are marketed as renewable technology -- you literally pump heat out of the air, ground or water surrounding you.

So long as these surroundings are large then the heat will be replaced by the sun as fast as it is extracted. You get say 3/4 of your heat for free.

We could say that heat pumps are three quarters renewable could we? does that count?]]> http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1565 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1565 Sat, 12 Apr 2008 19:45:58 +0100 tony
Posted by Simon H recently:-I started down the same route thinking which heating system is best. I've now to to the conclusion tony mentions above - none.

Here's why.... I've worked out using some spreadsheets and expected U values that by insulating properly I can get my heating demand down from 17.5kW to about 2kW when it's 0 outside. That's by using cavity wall insulation AND external wall insulation, having 300mm loft insulation, getting every nook and cranny and under the floors air sealed and insulated. Air sealing is very important - I found out that for house of my age/size (1960's) - I'll be losing over 6kW in drafts! I may add a 3rd pane of glass on top of the existing double glazing (which needs a lot of work on draft sealing as there's light visible under some of the windows - fitted in 2003!!!!??)

Once the pressure tests are showing the house isn't leaking too much air I can stick in a mechanical heat recovery system. The idea being that instead of using an extract only in the kitchen & bathrooms, you stick in ducting and run the "wet air" through a heat exchanger and get about 80% of the heat back that would normally get pumped outside you bring the pre-warmed fresh air back into the lounge/bedrooms. Why? If I ventilated naturally I'd lose about 1.6kW of heat to get the required air-changes to stop condensation. By running an electric fan using about 50W I reduce that heat loss to 300W. (Remember I started off with over 6kW).

This means that remaining 2kW of heat I need (on only the coldest days) most will come from cooking, appliances and body heat. With an additional top up from something else. For now I'm leaving the old gas central heating in, until I find out how much heat I need once things are insulated properly. I may add a smokeless (mmmn??) wood burner , much smaller heat pump, or just stick with a high efficiency condensing boiler for now. My current boiler is non condensing but still 80% efficient - fan assisted and has auto ignition (no pilot light continuously burning gas) about 15 years old so no need to rip it out just yet.

I've gone the insulation route as I expect it to cost around £10,000 but have no running costs and can be done job by job as I have the cash. Going for a heat pump will cost about £12,000 up front (£4,000 pump, £5,000 borehole, £3,000 underfloor heating and fitting) and still cost around £1,000 a year in electric bills just for the heat pump. The £10,000 on insulation has a 9 year payback. Or a return on investment compared to leaving the money in a saving account of 8.6% tax free. (I save £866 a year on my heating bills for my £10,000 investment).

Simon


We may edit the above as we develop the thread.]]> http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=2285 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=2285 Mon, 04 Aug 2008 13:36:50 +0100 ludite
I suggested that perhaps opaque glass could be used on a south facing side, to make the most of passive solar gain, but prevent you overlooking neighbours houses.

Fostertom sensibly pointed out that you can't see views through opaque glass.

This brings me to a dilemma.

The cottage we hope to move to is screened from the south by a low range of outbuildings. Our view to the North and West is fantastic - but it is also where the worst of the weather comes from.

I won't be alone in this. People living in barn conversions ( Barns were built to protect the farmhouse from the worst of the weather) probably have the same problem. As will people in new builds (where the planners have stuffed as many houses as possible on to a site, regardless of their orientation).

When I specified to the two architects we employed, that I didn't want any doors on the north side - or any large windows (because of heat loss). They looked at me as if I was a 'sad old Ludite', and gently explained that:

Modern glazing/insulation is so much better these days, you can have doors and big windows (to make the most of the views) any where we put them - including all over the north side. . . . . .

I don't believe them:cry::sad:

Is it me? Who's right? The experts? or little old 'refusing to keep up with the times' me?]]> http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1383 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1383 Mon, 10 Mar 2008 22:11:22 +0000 Henry Norton