RSJs

by Justin
(Cardiff)

Hi,

I am about to install support for a full length dormer, this will be a RSJ.

On architects plans RSJ goes into chimney breast, I seem to remember this unexceptable practice with solution being, RSJ into party wall opposing end supported via a stud partition.

Would very much appreciate some clarity.

Thank you

Justin

Tie Beams

by Brian
(Liverpool)

I am thinking of boarding out my loft space (storage only).

The loft is purling design (i think this is the right spelling), anyway on top of the joists I have tie beams running at right angles to the ceiling joists

Would it be wise to board on top of these?

I would have to add extra 4x2 so the loft boards would span the area.

This would then create a gap between joists and new floor.

Is this ok to do?

Brian

Binders and joists

by Simon
(London)

Hello,

I'd like to use my loft for storage.

It's a typical mid-terrace rafter and purlin design with four 4x2 angled struts running off a binder and four 4x2 tie beams.

I've already laid a tongue & groove chipboard floor but looking at your site wonder if I should possibly take this up and add a 2nd set of thicker floor joists for strength.

However, the 9x3 binder runs down the middle, so my question is how would I add in new joists, if they are taller than 4 inches they won't fit under the existing binder?

Many thanks,

Simon

Loft Conversion Purlin & Rafters

by wayne
(stoke)

Good evening, I am in the deciding process as to if to do a loft conversion.

I have the purlin & rafters design as our house was built in 1946.

It is a semi-detached. My question is, all the framework below the purlin (which consists of four 4x2 struts and two 3x2 horizontal joists) would be in the way of any conversion.

Would it be possible to remove! or move them as to gain more floor space?.

Could the 4x2 pieces be made vertical, so that the purlin is supported vertically to the floor beams rather than at a angle?.

I have attached a photo to hopefully show it more clearly.

double or triple?

by Peter
(Essex)

Hi, I can find the specification of single timber joists and their respective clear span / timber grade - where do I or can I find the same sort of detail that will tell me how far a double or triple 4x2 c16 timber joist will clearly span?

Planning A Loft Coversion / Joists

by Chris Walton
(Tyne & Wear)

I am going to do a loft conversion and I wanted to know what sort of joists I need and how are they installed?

Loft Flooring

by Alex
(Northern Ireland)

Hello

I would like to floor my loft for storage. Can I just lay boards on top off the rafters?

Someone I work with said these have to be at least 6"x2", but mine our only 4.5"x1.5".

If this isn't OK to do, how can I go about it?

Also would this be expensive to do?

My house was built in the 1930's the loft is approx 15ftx8ft.

Structural Steel Straps.

by Paul Sainsbury
(Shrewsbury)

Hi,

I am about to start work on a loft conversion. My loft is unusual in that the height from the floor to the apex is 18 feet. It is a mid-terrace house.

Currently there are two 9 by 3 inch timber biders that go in between the gable walls at approx 8 ft height. I want to have an open feel, therefore I have decided to not put a celing in but to insulate and platerboard all the way to the apex.

My question concerns the timber binders. I have been told that these can be replaced with steel rods or straps that will be way more discreet and almost unoticable.

Can you tell me where if this is indeed the case and the possible cost of installing two of these, also what diameter they are likely to be to replace the current 9 by 3 timber one.

Thanks very much in advance.

Joists

Hello

I am making a good storage place in my attic but started as I ment to go on - right.

The origanal joist run one way i have constructed a new frame of joists the opposite way at 300mm apart insulated it and then fixed 18mm chip for attic floors.

Does this method comply with the building regulations if I was to apply for permission at a later date?

Loft Flooring

by John Webster
(Nottingham)

Hi Jeremy....

I spoke to a builing officer chap today about boarding my loft ...so I can store light goods up there...he's told me I cant board more than 25% of the floor space...is this correct.. ive never heard of this before!!!

John

Heavy weight in a loft

Hello there, I am looking to buy a house but needed some help and came across this site.

The house has a large loft which is currently not used. The house is a new build and I was wondering whether you knew the weight limits for loft conversions.

I would like to create a snooker room, however, the snooker table weights just over 1000kg.

Is it out of the question to do this or is it infact possible?

Many thanks in advance for your help,

Jack

RSJ Steel loft Beams

by Dill Hussain
(BIrmingham UK)

Hello can anyone help..

I was wondering can you join to steel beams (with bolts) to form a long beam.. your help and advice is require.

Thank You

Loft Conversion Support Beams

by Ken Cameron
(Farnborough, Hants)

Hi There,

We were granted planning permission for a loft convertion in our bungalow for two bedrooms, an en-suite bathroom and two dormer windows a couple of years ago.

We never proceeded with the project as the building regs needed us to underpin the internal walls to carry the supporting beams as the size of the beams needed if sat on the external walls would have projected through the roof line, and we were not allowed to trim the ends of the beams at an angle.

Could you let us know if modern technology has now developed a smaller beam that would carry the same load and allow us to span across the external walls and not progect through the roof line.

Regards

Ken Cameron

Moving the joists that span the roof

by Dougie
(Scotland)

I'm doing loft coversion for storage can you move the joists spanning across the timber roof can you raise these any higher so you can stand up?

loft conversion joist size

by Jon
(South Wales)

Hi. I have reviewed the trada span table to acertain new joist sizes for the loft. Whilst the info points towards a 170x75mm to do the job, do you know of any other strength class timber that would be less than 170mm and perhaps span further?

Floored And Lined Loft.

by Tommy Gallacher
(Scotland)

About ten years ago I floored and lined the loft for storage only.

I am now selling and applied for a letter of comfort from the council.

They have given me 2 options either rip it out or have remedials done which include roof vents-insulation with a plastic membrane and a report from a structural engineer.

Are all the remedials necessary as rhe space is only used for storage?.

Loft Conversion Steel Columns

by Irina
(London)

Hi,

We are doing a loft conversion into our 1930's built house, to give us another bedroom.

We have 3 steel columns installed (1x 203x203x46 and 2x 152x152x37)but just had the council inspectors visit and he's not happy with the fact that the middle 152x152x37 column is about 10cm outside the chimney stack.

Though our engineer advised that the loading on this column is not a problem , the inspector wants us to move the column as this is too close to the chimney (previously agreed that as long as it doesn't touch the chimney would be ok)(Note that the actual beam arrangement is the only one to accomodate staircase).

The size of the new room is 25 square meters and we already have the 3 columns; I'm not an expert but putting on another steel column to sustain end of the 3 existing columns won't be far to heavy for walls?

Would you please be able to advise, is there a regulation to say that the steel cannot go close to the chimney stack - please note that the chimney has been removed years ago and nothing is left out of it.

Thank you very much

Regards,
Irina Gheorghiu

General Inquiry - Loft Storage & Flooring

Hi

I have boarded out my loft the joists were originaly 6" x 2 1/2" but have been increased to 8" x 2 1/2" to increase strength and to level them up with 18 mm chipboard flooring ( 2400 x 600 )on top - all above glued and screwed ,glass fibre insulation has been fitted between the joists.

The rafters are 5" x 2" with 3" kingspan insulation between with 1" insulation across with 9.5mm plasterboard to finish. at each eave new stud walls have been constructed 1/3 of the way in (from centre of house to eave) made up from 4" x 2" doubled up at sole and head with uprights at 16" centres.

The original plan was to use this space for a storage/ play room ( ie soft seats, games consoles etc ) with a pull down loft ladder but i may need the space to be a living room as a less able relative may have to move in and use the original living room as a bedroom.

I am a qulified joiner hence the work already done what i cannot seem to find out is if i install a staircase , velux windows, escape ladder, mains fire alarm and a firedoor at the bottom of the stairs would all this be enough to comply with building regs or do they only relate to the conversion of space for bedrooms and bathrooms which i do not want to put up there.

Your advice on this would be much apreciated.

trussed loft (w shape)

by kc
(southampton, uk)

I have been told to get steel girders in to convert my loft safely.

But with the angle of my roof I can't do that, and I don't need that much space.

Can I just add in joists to the smaller joists , add a wall down and then put in seperate joists over the ceiling to support all together.

So a row of uprights on the sides and two rows above the ceiling - along with several beams, to join two sides together?

wouldn't that do the job?

Joists

Hi there

I wonder if you could tell me the size of timber is needed for my floor joists for my loft conversion.

At the moment they are 4" by 2" ,with a span of 25 ft but there is a load bearing wall though the middle of them.

Support For New Loft Floor

by Dave
(Nottingham)

Hi,

I'm thinkin about laying a new floor in the loft so that it can be fully load bearing and comply with building regs.

The house is a 1930's semi Purlin & rafter loft with purlin's holding the roof rafters up and purlins/binders below them in the eaves holding the joists together.

These lower purlins are effectively sat on a total of 5 supporting walls (between mine and the neighbour).

Will I be able to use joist hangers on these lower purlins to support new joist between them?

If not I assume I will need some sort of steel beam to run alongside these lower purlins instead....how would a builder normally get these in the loft?

What rough sort of cost could I expect?

Thanks

Dave

Joinst Centre Span

by Steffen
(Gloucestershire)

Hi,

I'm doing my investigation to put down some loft flooring.

All the loft board packs that i have seen, mainly B&Q and Homebase, require the joist centre span to be no more than 450mm wide. My joist centre spans are around 560mm.

Can you suggest what i should do in this case?