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Portal Frame House


K78

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I have seen a few threads on here regarding converting existing portal frames into houses. But none on building with a new one like the barnhaus concept. 

 

Would it be a issue getting a house like this to meet building regulations?

 

It looks like a huge saving in foundation cost. 

 

A steel portal frame would cost less than my quotes for feature trusses.

 

https://nacsba.org.uk/wp-content/uploads/2013/10/images_shoestring_18_shoestring13_ed-green.pdf

14043AFC-1EDD-4A81-9357-5956C9EE29D3.png

540B5C7C-7D1E-4179-AFAA-2C88165E6D73.png

55AFEBFB-CF96-497F-822A-C9970D970690.png

Edited by K78
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  • 1 year later...

This is the sort of design we are planning to use. I cannot see an issue with building regs as this is how many new offices are built.

 

What were the concerns you had about the regs?

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We are building with a new hot-rolled steel frame like this, though technically it is as a part of a 'conversion'. Frame supplier is one that usually builds barns and sheds.

 

AFAIK there is no inherant building regs issue with a hot rolled steel frame and loads of buildings of all kinds are made this way, though it will need all steel protected from fire e.g. by being enclosed or intumesent painted.

 

The Barnhaus is an interesting concept to provoke discussion, and I think in general these kinds of building methods should be more widely considered for residential, however I'm skeptical about the barnhaus pricing and some of the details. I'm not clear whether the specific design has been ok'd from a structural, insulation, or longevity perspective. The steels are whopping thermal bridges which might lead to condensation problems, and the combination of straw and steel seems dubious and a gimmick. It's unclear how they'd planned to insulate the roof. Better I would have thought to have the insulation layer on the exterior e.g. via standard insulating sandwich panels like the Kingspan KS1000RW (which we are using).

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Hi Kxi

 

I would love to see or hear more about your project. We plan on using a hot rolled portal frame with ks1000rw roof and possibly walls. May use a different profile on walls depending on planners. 
 

How do you plan on building your walls?

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@PDR

Some overall background on our project - before we had settled on a build method.

https://forum.buildhub.org.uk/topic/7201-hello-from-berkshire/

 

Steel frame with KS1000 cladding was definitely not what we started out considering, but various constraints pushed us that way and now we are committed - but nothing actually rising out of the ground as yet. We considered I think every building method known to man. To be honest at the stage you are at - I would not get wedded to a given build method. Realistically the planners only care about the outer skin rather than the internal construction.

 

The overall build method:

  • Hot rolled steel frame with a first floor of hollowcore + structural topping. 
  • Roof and first floor walls clad with KS1000RW 150mm quadcore - so the thermal and airtightness layers wrap around all the habitable parts of the building (mainly the exterior). I.e. first floor walls from outside to in: kingspan panels (150mm) - big empty space - inner plasterboard. So it is still fairly simple at least
  • Ground floor walls are non-supporting (steel frame does the support) and are block skin with timber frame inside infilled with PIR - our ground floor walls can't be kingspan panels as they have to have fire compartmentalisation against some barn areas (which likely won't apply to you)
  • First floor soffit and ground floor over slab insulated with something like Kooltherm - again - the thinnest we can manage
  • Loads of giant pad foundations set deep in the ground (we're on clay + chalk and also have to go below the existing building foundations), then a big slab over the top of that

 

Reasons why we went with steel frame + cladding:

  • Head height - planning means we couldn't go up and so we needed to save every cm we could and the KS1000 is about the thinnest super insulated roof we could get. Though we're actually now putting it on huge wooden purlins so it's not that thin... Also a mass timber frame like glulam would have meant beams that were far thicker than steel and so head height problems.
  • Concrete first floor - a large part of the ground floor is agricultural use - so could have all sorts in there. So we wanted a very solid fire seperation between ground and first floor - so concrete. Again desperate to save head height so the hollowcore is arranged set into the steel beams rather than sat on top of them in a 'slim floor' approach - they usually use this on very tall buildings to get 11 floors rather than 10. A concrete floor is most simply done with a big steel frame, though there is some interesting stuff being done with wood+concrete composite inc CLT - this was tempting but is a bit experimental.
  • Single supplier - we wanted a single suplier who could do multiple parts of the main structure because that gives a comfort factor to a first time self builder like ourselves. Steel frame + cladding is a common package. As it was we really did try engaging with suppliers of other systems - especially timber frame - but we were generally too odd a project I think and most didn't seem to want to engage
  • Cost - we're getting the frame and cladding built by a firm that makes maybe 200 giant sheds a year. In theory this should be a cheap approach and working with suppliers who work to clear and slim margins. However, some of the issues applying the method to a house mean more money needs to go on designing details and other things. We are not a simple single storey portal frame, I suspect if we were you could get it down MUCH more cheaply. Weight is also an issue - a more lightweight timber frame would probably have been cheaper groundworks. Using the KS1000 in particular has big savings for the roof - the whole roof envelope is probably less than most people would pay for just a roof covering (e.g. tiles or metal sheet) BUT this isn't perhaps a huge cost in the grand scheme of things
  • Apparant neatness & simplicity of envelope - the cladding seems an elegant and simple way of achieving everything you need in a building envelope. So simple! But, as it turns out it's simple if you want to build a giant single-storey windowless shed. Not so simple for a house...
  • Design - luckily we don't have too many 'visual' restrictions from planning and we actually like the industrial nature. I.e. the look of steel + cladding was not a barrier to us, but might be for others

I suspect had we not had some of the constraints we did, we might not have picked this method, but we might have.

 

Some problems & solutions:

  • windows and doors - putting proper windows in the KS1000 and having them thermally decoupled from the frame - complicated. Maybe it's just as complicated as in any well insulated and airtight house, but it seems no-one has done it before and everything feels like you are designing the first space shuttle. We are going to use the Kingspan DLTR 150mm 0.8U rooflights in quite a few places - you CAN flash in 'normal' rooflights, but it's hard and what we wanted (glass roof areas) was not going to be simple at all
  • thermal bridging - our very weird mixed-use shape means we have numerous giant steel beam thermal bridges through the insulation layer. This is handled with liberal use of armatherm structural thermal breaks, so it's not impossible - just a constant thing to be aware of
  • architect familiarity - Unless you get a shed builder to design it, your architect will have never worked with anything like this and there will be a lot of learning which adds cost and risk. They may just flat out refuse, not least because it reduces the flexibility they have to do architecty things. (You not be using an architect I suppose)
  • Detailling quality - in particular the flashings - these all look kind of like an industrial unit - and there's not much you can do about it. If you like that great - but you can't really change your mind later
  • Limited on what you can attach to the panels - they are thin steel sheet so attaching stuff to it is problematic. For example we want a few large awnings attached for shading, and we have to create thermally broken brackets back to the main frame, which then poke through holes cut in the kingspan panels - it's not ideal. I.e. you have less flexibility about sticking on lights and stuff. Perhaps not a big deal
  • Wall depth - the panels are nice and thin for the whole envelope - but they have got to be attached to cladding rails, then these cladding rails need to be attached to the main frame. In a warehouse generally everything is left open on the inside, but in a house you will likely want to cover this all up - so your 150mm wall which gives a 0.12U ends up being a 350mm wall anyway just it's mostly hollow. Not a huge issue, but just worth remembering that just because the panel is thin, doesn't mean your wall will be
  • Damage - the panels can get damaged by people bumping them and they are not repairable in an invisible way. I think you often see people putting brick skins in high traffic areas or on the ground floor to reduce ground level damage. As it happens we can't use them at ground floor level any due to fire compartmentalisation issues - which I suspect a normal detached house would not have an issue with
  • Resale - metal clad walls are very uncommon on houses in the UK and I suspect would impact ease of selling. I'm sure some people would think it was great, but others might not. In the US you'd probably have less of a problem. We aren't ever going to sell, so it's not a consideration. It probably depends on how much you mind about creating a building that is unusual. 
  • Baked - Browsing the forum you will also see a potential issue with decrement delay if using these kind of panels, but....we judged (but did not calculate) that issues such as good solar shading are probably more important. I guess we can report back next year whether we've been cooked or not.
  • Sound - kingspan panels provide little sound insulation - that's not an issue for us

So in short - it might be better to think of something other than KS1000 panels for the walls if you can. You will still want to have the insulation on the outside of the steel frame though (though one buildhubber - Ian built his timber frame barn conversion inside and existing steel frame). From a planning POV i don't know. I suspect a metal roof wouldn't cause much objection, but metal clad walls might raise more eyebrows - but i wouldn't want to pre-judge it as there are so many factors there.

 

Overall, I'd keep an open mind about build method at this stage. Timberframe (e.g. twin wall), CLT, and mass timber (e.g. glulam) all other interesting options to consider and you could still end up with KS1000 for the roof, or metal cladding all over if you wanted.

 

 

Edited by kxi
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I'm currently working on a conversion of a two storey barn into a house for someone - we are just about to get the building warrant approval for it (just need to show a 10,000ltrs water storage tank)

 

I'd say the main issues we've had are easy to avoid with a new build, they're more conversion specific.

 

So the biggest issue we've had is really getting an engineer to prove that the structure is suitable (we didn't have access to the original drawings or calculations from the manufacturer) but we found that the foundations weren't what they should be and the ground floor slab wasn't thick enough either.

Then the timber midfloor wasn't properly supported.

 

Putting opening rooflights in seems to be an issue, all the panel manufacturers are very resistant to that (although this place has two already installed!

 

My biggest worry is the thermal bridging over the portal itself, as we aren't using an isulated panel system, we're effectively building a new insulated inner leaf which will take the windows etc too...

 

and then we have the buildability side of how to put it all together!!

 

however, it'll all be worth it in the end, the views from the place are amazing!

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Wow @kxi thanks for the comprehensive reply. Maybe I should have said, our reason for choosing steel frame and ks1000rw is because I am a steel and cladding designer/detailer. So I have an adavantage and will do all the design work and drawings. Brother in law owns a fabrication shop and my brother in and industrial Cladder. So many advantages.

 

we are looking at making the walls narrower by fitting the cold rolled rails between the columns, then we will use a metal stud internally for the plasterboard fixing... we hope.

 

You are correct about opening roof lights. No one likes them in the industry, but you can do them and if you are doing that I have a contact who is pretty much the best of the best at fixing and sealing them, so happy to pass details if you need.

 

For your floor did you look at a metal deck with concrete as an option too? Nothing wrong with precast, I do think deck and slab is cheaper though.

 

thanks 

PDR

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On 03/07/2020 at 00:33, PDR said:

I am a steel and cladding designer/detailer

 

Ah.

I'll be asking you lot of questions then.

 

On 03/07/2020 at 00:33, PDR said:

we are looking at making the walls narrower by fitting the cold rolled rails between the columns

 

Yes, that's our plan, but it still leaves a large void (200mm ish?) between the external panels and internal board that I can't help thinking should be better used. 1,000 small cupboards perhaps. There's also the issue of dealing with flanking sound coming through the void between the rooms, so we will either try and bring the stud walls 'into' the void, or stuff it with something at the internal wall junctions. Havn't really though about that yet.

 

On 03/07/2020 at 00:33, PDR said:

For your floor did you look at a metal deck with concrete as an option too?

 

Yes, but went with precast for perhaps not good reasons. Our main aim is to reduce head height and with precast I found the 'slim floor' method to sit the precast level with the steel beams. With precast sat on the bottom flange of the beams. e.g.

 

image.png.281f79422112b679acb7e8f2a6ea2b4e.png

 

I saw this first with precast and I think the combination stuck with me. A metal deck with cellular beams version:

https://www.kloecknermetalsuk.com/westok/products/ultra-shallow-floor-beam/

 

I think I was keen on precast hollowcore because:

- I was (naively) concerned about longevity of a metal deck vs precast i.e. once the exposed metal starts to go, presumably that's it? I suspect this isn't an issue in reality. The first floor will be over an agricultural space but it's unlikely to ever be a corrosive environment like cattle, but precast felt safer. The soffit is in any case covered by 150mm of insulation and fireproofing

- It may have been we could get a slightly thinner floor with precast - don't remember

- The idea of how hollowcore works was so clever that it was seductive

- I never costed the two - had I done so things might have been different, but precast didn't seem so expensive to be a problem

 

On 03/07/2020 at 00:33, PDR said:

roof lights. No one likes them in the industry, but you can do them and if you are doing that I have a contact

 

That's very helpful thanks, though I think now we mentally switched to the KS1000 DLTR 0.8s we will probably stick with them. We only need light not ventilation. The plan wasn't for regular opening rooflights but for a 1x20m strip of glass roof set above a long corridor. The plan was to use lamilux PR60 glass roof set into the panels for this, but 

a) expensive

b) lots of teeth sucking about how to fit it. There was a solution but no-one was confident (see below)

c) big solar gain problem that can't easily be mitigated

 

image.thumb.png.6487d2cd99c466b44b502d0fa7bb5c15.png

 

 

So we're instead planning on using 6 or so KS1000 DLTR 0.8 panels. You really can't see through them, but they are much cheaper and easier to fit, and have a diffuse light without as much solar gain.

 

 

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@PDR checking notes, it looks like the SE was slightly keener on precast than metal deck for the 5m spans we needed, in terms of overall weight and and thickness required, so that probably influenced it. Metal deck needed propping for 4 weeks but that wouldn't have been an issue in our case.

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On 20/04/2019 at 17:27, K78 said:

I have seen a few threads on here regarding converting existing portal frames into houses. But none on building with a new one like the barnhaus concept. 

 

Would it be a issue getting a house like this to meet building regulations?

 

It looks like a huge saving in foundation cost. 

 

A steel portal frame would cost less than my quotes for feature trusses.

 

https://nacsba.org.uk/wp-content/uploads/2013/10/images_shoestring_18_shoestring13_ed-green.pdf

14043AFC-1EDD-4A81-9357-5956C9EE29D3.png

540B5C7C-7D1E-4179-AFAA-2C88165E6D73.png

55AFEBFB-CF96-497F-822A-C9970D970690.png

Great idea and all very doable. They make fantastic spaces / volume at a realistic cost.

Couple of points or so. A steel portal frame is a different animal from standard domestic construction. They tend to sway about more. When the wind blows on the side of the building it sways sideways. When you get heavy snow the roof flexes downwards. This is called horizontal and vertical deflection respectively.

Very generally on an agricultural type portal frame the limits Engineers set on deflection are slacker than those used when you have finishes on the inside that are attached to the frame or brickwork say on the outside. Some cladding manufactures also specify deflection limits for cladding as if the structural frame bends too much it over stresses the cladding fixings, your roof leaks and voids the warranty on the cladding.

For example on an agricultural building with a column height of 5.0m you could set a limit of column height / 100 = 50mm allowable sway under the design loads.

If you have a house you probably want to reduce this to below column height /300  or column height/ 500 which is ~ 10 – 16mm. Much better for your internal finishes.  If you are having one end as a barn (agricultural use and the other end as a house then you either need to decouple the two or maybe consider designing it all for the more onerous deflection limits.

If you are comparing prices for portal frames always ask what deflection limits the frame is designed to. Legally all frames need to be safe (not fall down and kill people / animals)  but the deflection limits are more flexible. If you ask for this information you can compare apples with apples in terms of cost.

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Just came across this kingspan case study using insulated sandwich panels on a French house, which I'm pretty sure is the first use of them on a purpose-built detached single dwelling I've ever seen

https://www.kingspan.com/gb/en-gb/products/architectural-facade-systems/case-studies/maison-if

 

Visually I'm sure it's not to everyone's taste, but a bold choice. Intersting that kingspan seem to be marketing it, suggesting they see potential in the residential market.

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58 minutes ago, kxi said:

Just came across this kingspan case study using insulated sandwich panels on a French house, which I'm pretty sure is the first use of them on a purpose-built detached single dwelling I've ever seen

https://www.kingspan.com/gb/en-gb/products/architectural-facade-systems/case-studies/maison-if

 

Visually I'm sure it's not to everyone's taste, but a bold choice. Intersting that kingspan seem to be marketing it, suggesting they see potential in the residential market.

 

Looks like the back diesel generator installation on a large industrial site. 

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10 hours ago, kxi said:

Visually I'm sure it's not to everyone's taste, but a bold choice. Intersting that kingspan seem to be marketing it, suggesting they see potential in the residential market.

Difficult to find something that is to everyones taste, but I like it and find it a lot more interesting than the neighbouring house.

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  • 1 month later...

@kxi 

 

Thinking about using a steel portal frame for my build. I see you mentioned thermal brakes to prevent heat transfer into the steel within the building. Have you got as far as getting a price quote for the thermal brakes. Trying to get a cost per column for my costings sheet. Cheers 

 

 

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  • 1 month later...
On 28/08/2020 at 23:15, gavztheouch said:

@kxi 

 

Thinking about using a steel portal frame for my build. I see you mentioned thermal brakes to prevent heat transfer into the steel within the building. Have you got as far as getting a price quote for the thermal brakes. Trying to get a cost per column for my costings sheet. Cheers 

 

 

 

Hello, only just got initial costing for these. Expensive. Estimated price is £7,000 for about 24 x 50mm thick armatherm FRR pads. So £350 per pad. Seems *quite* a lot. This was an estimated price from the steel frame supplier. Our building is unusual in that it has so many, so would be less of a cost in something more a normal shape.

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29 minutes ago, kxi said:

Hello, only just got initial costing for these. Expensive. Estimated price is £7,000 for about 24 x 50mm thick armatherm FRR pads. So £350 per pad. Seems *quite* a lot. This was an estimated price from the steel frame supplier. Our building is unusual in that it has so many, so would be less of a cost in something more a normal shape.

 

That is expensive, i was looking at the Armatherm 500 product for the thermal break in a concrete block wall, and got a direct quote from Armadillo (01274 591115) yesterday for 100m length total.

 

2000mm x 100mm x 50mm Blanks of  500-160 - £20 per unit + VAT

2000mm x 100mm x 50mm Blanks of  500-250 - £30 per unit + VAT

 

I can't see how 50mm FRR pads is that much more expensive, i would contact Armadillo directly

Edited by Moonshine
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  • 9 months later...

Hi all i am looking for any / all information on the portal frame building system you all seam to have looked at unfortunately i am drawing a blank & hope with your help will be able to make some progress.

It seams a natural progressing to me having erected many farm buildings just like this.

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@Pochlin We are using a steel frame, though not a portal, as a) it had to be monopitch for planning reasons, b) needed a concrete first floor.

 

Our frame, erection, cladding all provided by an experienced shed-basher from the list at https://www.ridba.org.uk/

 

The frame aspect is pretty standard (apart from the thermal breaks), but the cladding ... not so much. We chose to try using standard Kingspan KS1000RW quadcore insulated cladding as it seemed a neat idea. Turns out it is fiendishly complicated to get this to the airtightness + thermal bridge-free levels we wanted, mainly due to difficultly sorting out how the windows sit in the cladding. This is partly because no-one really does this, so everything is worked out from scratch. If you were going for standard airtightness and thermal bridging it might be easier though. One big advantage of this approach is you can put rooflights anywhere you want easily - as long as you are happy with the standard kingspan plastic ones (i.e. that you can't see out of).

 

In that, a different cladding/wall approach might be better - but you've still got to support the insulation and windows somehow.

 

One day when it's all done I'll be able to give a better post-mortem on the approach, but suffice to say, right now in the midst of things, there are quite a few challenges which make me wonder whether another method would have been better. A wooden portal frame e.g. glulam, would avoid a lot of the thermal bridging issues and mean you could probably have the insulation layer in-line with the frame, rather than fully outboard or in-board. However, the main advantages of a 'big frame' approach inc. portal is you can get huge open spans as you would want in a barn or industrial space. If you aren't going to use these spans in a residential building, then it's perhaps better to consider a more conventional method.

 

Resale may also be a consideration, anything non-standard and/or industrial looking could be a bit problematic, if resale matters to you.

 

I certainly wouldn't want to put anyone off considering it, but just to flag up there are complexities. One might say the near total lack of steel-frame residential buildings is a bad sign for the method, but I suspect it's largely to do with a) the potentially 'modern' industrial look of the resulting building (which many people would not like or not be feasible from planning POV), b) bad reputation from terribly designed mid-century steel frame houses, c) huge conservatism in UK house building.

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@Pochlin

For example, looking at the RIDBA 2021 awards shortlist, amongst the cow sheds and warehouses there is a residential building:

https://www.ridba.org.uk/ridba-building-awards-shortlist-2021/

Which looks like it could be a single story steel frame that someone has then wrapped in a conventional wall and roof construction, perhaps with a low block wall that the windows are resting on.

 

From what I've seen, most steel frame in UK is now barn conversions, probably under class Q, rather than new build. Not least because of the planning issues with doing any new build in the countryside.

 

I don't have the examples I've seen before to hand, but having a quick check now on The Modern House:

https://www.themodernhouse.com/past-sales/southborough/

Looks like a steel frame cunningly concealed

 

Bit of 60s glulam

https://www.themodernhouse.com/past-sales/clayton-windmills/

 

and the mega

https://www.themodernhouse.com/past-sales/hapsford-stables/

Which seems a mix of stone wall and steel frame - with concrete encased steel columns I think

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  • 10 months later...

Hi..

 

Im a newby, attracted by my search for information on Steel Portal Frame for residential use.

 

I am a retired Carpenter/joiner and looking for a way to build a live/work (Hobby use)  property for my remaining 40 years.

 

I loved the idea of 4 or 5 Steel portal frames at 8m wide and 3-4m spaced giving me 100m2 workshop+ 1st floor of same for living.

Quick to fabricate, minimum footing pads, quick erect + composite panels roof and walls.

Much like others here above I believe.

 

As a Carpenter I initialy looked at Timberframe but wanted an idea of Steelframe costs to compare.. and that is where I got stalled.. 10years ago..

 

As I had Sketchuped my simple designs.. I spent an hour showing it to a Technologist. He never got back to me and screened my calls.

Next.. an Architect & Engineer.. same again..  and then again... and again... 

No one will talk to me...   and because they wont talk to me I have no idea.. Why???         Truly exasperating and I learned nothing..

 

I do still keep trying occasionally, changing my story each time a bit until it's almost total rubbish..

 

Perhaps, as is mentioned here, Portal Frame is considered only Agri or Commercial and..  well.. different folks for different strokes.. 

I've been turned away by Steel Fabricators (Show me your Drawings..) and Kit suppliers..  (Not for Residential use).. etc

 

It's been a couple of years in this thread so I am curious if any success has been had and what hoops had to be jumped through..  Particularly PDR in

Herefordshire and to enquire whether your services are for hire..

 

Thanks

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11 hours ago, Marlin said:

Hi..

 

Im a newby, attracted by my search for information on Steel Portal Frame for residential use.

 

I am a retired Carpenter/joiner and looking for a way to build a live/work (Hobby use)  property for my remaining 40 years.

 

I loved the idea of 4 or 5 Steel portal frames at 8m wide and 3-4m spaced giving me 100m2 workshop+ 1st floor of same for living.

Quick to fabricate, minimum footing pads, quick erect + composite panels roof and walls.

Much like others here above I believe.

 

As a Carpenter I initialy looked at Timberframe but wanted an idea of Steelframe costs to compare.. and that is where I got stalled.. 10years ago..

 

As I had Sketchuped my simple designs.. I spent an hour showing it to a Technologist. He never got back to me and screened my calls.

Next.. an Architect & Engineer.. same again..  and then again... and again... 

No one will talk to me...   and because they wont talk to me I have no idea.. Why???         Truly exasperating and I learned nothing..

 

I do still keep trying occasionally, changing my story each time a bit until it's almost total rubbish..

 

Perhaps, as is mentioned here, Portal Frame is considered only Agri or Commercial and..  well.. different folks for different strokes.. 

I've been turned away by Steel Fabricators (Show me your Drawings..) and Kit suppliers..  (Not for Residential use).. etc

 

It's been a couple of years in this thread so I am curious if any success has been had and what hoops had to be jumped through..  Particularly PDR in

Herefordshire and to enquire whether your services are for hire..

 

Thanks

Hello Marlin and welcome.

 

You'll get plenty help here.  There are a few folk that have joined since this thread was started. It's a guess, but some will be along shortly to contribute in terms of how you design this structurally for a domestic application and a few tips and hints on the insulation details and so on... and many more.

 

In terms of structural design the main difference between agricultural design and domestic design is the deflection limits you work with. In terms of detailing you have a bit more work to do to reduce cold bridging, detailing around the openings and damp proofing, all surmountable though. Think of it like an office building.. meets the same standards very much as a house requires in terms of environment and insulation.

 

Ok. To get you a bit further what about posting your sketches, make sure you dimension them; include the roof pitch,  show windows / doors and the heights you want internally, where you want the openings and how big you would like them to be. Also show the ground levels as this impacts on the column height down to the found as that is one key parameter when determining the steel section sizes. What kind of ground do you have, clay / chalk / rock etc.

 

If you want.. provide your location. You can give just the first part of your post code. Then we can see roughly where you are in the country. Also provide the site altitude and if close to the sea.. if next to a cliff or at the top of a long exposed hill let us know that and then we can get a handle on the wind and snow loading This will allow for example for folk to give you a rough steel size for the main portals and a ball park size / spacing for your steel purlins and wall rails.

 

There are many variants but you need to start somewhere! For your steelwork you can go the whole hog and work all this up to a full set of fabrication drawings, material and bolt list with numerical control files and then start farming that out to fabricators. All they need to then is to fabricate as they have no design input at that point. The numerical control files are a text file that is accepted by the software on most advance cutting and drilling set ups. Having these lets you go to big fabricators for a price too. But the NC files are not essential as most smaller fabricators just want a good set of drawings.

 

A good set of drawings comprises. General arrangement drawings. What are called assembly drawings.. these are drawings that show say beams with their end plates say and the weld information, a plate and shaft set of drawings. These are drawings of each individual plate and beam. Small fabricators may buy in the plates and shafts and make their money on the welding / painting/ supplying the bolts and so on.. again many variations on how you can go about this. Now that is a lot of drawings but we use software to do a lot of the heavy lifting and drawing production.

 

In terms of PDR the planners are interested in what it looks like from the outside rather than the skeleton of the building which is often covered?

 

Keep posting.. interested in your ideas.

 

 

 

 

 

 

 

 

 

 

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On 20/04/2019 at 17:27, K78 said:

Would it be an issue getting a house like this to meet building regulations?

 

No , easy.

I have done stacks of new steel portal frame buildings as offices and classrooms, and the same logic will apply to a house.

BUT the advantage of a portal frame is clear open space. If you have normal domestic subdivisions then the the walls provide support.

For anything of domestic scale a conventional construction is more likely to be best value, but if you want big spaces in any dimension then steel portals come into their own.

 

For the upper floors, my preference is steel z rails as joists, then decking. Against precast concrete is the craning operation without smashing the steel frame and especially any purlins.. I designed such buildings so that half the columns and beams were erected first, then the slabs put in, and then the rest of the columns and rafters, but this was for a very big  2 storey warehouse, and the costs would be prohibitive for a house.

 

I have not read the thread fully, so forgive any errors of understanding. 

 

Would I build my own house as a steel portal? Definitely, but it wouldn't look like a barn, but a boxy modern shape, and with big rooms and feature cut-outs.

I would avoid all the latest gimmicks, and also the ones that won't go away such as straw.

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9 hours ago, saveasteading said:

also the ones that won't go away such as straw

And wood burners.

 

There was a comedian on a radio show. She pointed out the many British (white English I assume) want to get off grid.

Her family came from an off grid society in the Punjab. House swap is the answer.

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Hi and thank you for your comments.

 

Hi Gus, 

My initial design for this project was very vague.. intentionally..  thinking the Designer would manipulate it into whatever it needed to be for the

permissions.  I have a plot in mind but have not approached the landowner until I had some sort of Drawings to show..

 

I had assumed everything above ground could be designed and within reason be 'signed off' but if I chose a new location this would only affect the Foundation..

I do not intend to build in any kind of extreme environment..  Regular flat(ish) ground probably.. Clay..  Nothing weird..  Probably a knockdown..  In the South east.

 

I refer you to my middle comment..     I cannot find a Professional to do the Design work for me..     

 

I am moderately competent with Basic Sketchup and have tinkered with other 2d CAD programs

or even Revit/Tekla but the learning curve is massive and assumes a knowledge level of Maths/formulaes I just do not possess.  I cannot design this myself and I had no idea

it would prove so difficult to employ somebody..

 

Saveasteading..  Are you in Construction.. Or the design side..        I am certainly interested in peoples experiences and choices/build details made (and indeed have my own list of preferences

which one day I hope to implement).

 

I dont know if Barnhaus succeeded as it was a 'Concept' contest I believe.. I think they are still going in Cardiff.

 

I'll try to attach some jpegs of my Portal Frame with my guesses at Steel sizes.  No particular consistency here..   Certainly beefier than Agricultural.

 

 

 

Barebones3.1.JPG

Barebones1.JPG

BB1 Frame corner detail.JPG

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