Loft Conversion - Gies a lift mate

The time has finally arrived for the steel to be lifted into the loft space.  This is certainly one job that couldn't be done myself and thankfully i have really willing and helpful family and fantastic friends who all came along on the day to help out.  Most importantly my friend brought his hiab truck along to do the big lifts.

You may recall from an earlier post that there were two 7m long steel beams and a 6m long flitch beam to be fitted into the loft.  The steel beams were split in to 1/3rd and 2/3rd sections which will be spliced together in the loft.  Each of the long sections of steel weigh 205Kg, the smaller 1/3rd sections weigh 100Kg each and the flitch beam weighs approximately 250kg.  These, combined with 10 of the 6m long C24 joists which needed to be lifted in meant that in total we need to lift approximately 1 tonne of materials into the loft space.

Thank heavens we had a crane! 

Before the steel was lifted into the loft the padstones and bearing lintels were fitted into place.  These will take the weight of the steel beams and the loft floor which will be hung from steel beams.  This will mean that the weight will be transferred down the walls and onto the foundation of the building.  At the other end the steel beams will rest on a larger lintel section and steel shoe which will be bolted to the party wall.  Again this is designed to transfer all the weight down to the foundations.

The 'easiest' way to get the steel, flitch beam and joists into the loft space was by opening up the roof, lifting each item up and sliding it into the loft space.  We used the winch in the loft space and a steel roller plate to make it a bit easier to pull stuff inside.

From the inside

This is the flitch beam being slid into the loft space through the opening.  The crane took most of the weight and there was two people inside pulling the stuff in.  Once over half of the beam was inside the loft the chain was taken off and the winch inside the loft was used to help pull the beam inside.

I love how this picture makes it look as if i simply slid the steel beam into the loft space.  However, the reality was quite different and it was a heavy going 4 hour long job just to get it all up and in, with an hour and half each side of that to open/close the roof and erect/dismantle the scaffold.  If it hadn't have been for my mate and his crane this job wouldn't be happening and if it hadn't been for my brother, father-in-law and a few other friends the steel wouldn't have made it into the loft.  The exact opposite of Dae It Yersel :-) 

The short section of steel is now in place, resting on the lintel bearer.  The next steps are to line and level everything up, fit the steel shoe then lift the larger section of steel into place and bolt it all together.

Thank heavens for family and great friends.

The best winch I've ever had

For the next job I had to fit a 1.5m long K9 lintel weighing approx. 125Kg in the loft to provide some support for the steel beams which are hopefully going in this week.  The only problem was that the lintel had to be lifted 2.5m up into the loft space!  

To get the lintel up onto the top landing i simply strapped it onto a barrow and wheeled/bumped it up the stairs.  Seemples! 

I had previously lifted a smaller lintel up into the loft by sliding it up the planks of wood next to the ladder, however, this wasn't an option for the larger 125Kg lintel.

and here is the lintel in it's final place, resting on padstones at either end.  The steel support bracket/shoe for the steel beams is just sitting in place prior to being measured, marked and bolted to the party wall.

But how did you get the lintel up there i hear you ask.............

.......I used this electric winch, which i borrowed from my brother-in-law (but don't tell him, he doesn't know i borrowed it yet).  I bolted it to its swing arm and simply sat it across the newly fitted C16 collars above the loft opening.  After that i just lowered it, hooked it onto the barrow and pulled the barrow and lintel up the planks of wood.

Hey presto!  One lintel (and barrow) winched up into the loft space.

I wonder if this is how Stanley Kubrick lifted the monolith into place.





p.s. for my non-Scottish readers - a winch is another name for a kiss.

Loft Conversion - Collared

To provide a decent amount of headroom in the new bedroom the collars which spanned across the rafter at approximately 1.9m were moved upwards to 2.4m but renewed in C16 structural timbers 145mm x 47mm, bolted through with M12 Grade 8.8 bolts and toothed plate connectors.

This is the  1.9m height of the collars as the roof trusses were originally constructed.

The new C16 collars were cut and fitted in place temporarily and then string lined, levelled and marked to ensure a level fitting across the width and length of what will be the new ceiling.

The existing collars remained in place whilst the new ones were fitted.  This made the fitting a wee bit awkward but it meant there was no movement in the roof trusses at all.

Once the new collars were lined up and marked, 13mm holes were bored through them and the existing trusses,toothed plate connectors were fitted between the timbers and then the M12 bolts were used to bolt the timbers together.

Once sufficient torque had been applied to the bolts and the toothed connectors were bitten into the timbers the old collars were removed and set aside for reuse elsewhere in the conversion.

The extra 500mm in height makes a considerable difference to the feeling of spaciousness already.

Loft Conversion - Deforestation in action

This is the first delivery of timber and whilst they look like pretty substantial timbers, these are just the 9" x 2" packers required to pack up and out the existing 6" x 2" joists.  These 'packers' will then be sandwiched in between structural 9" x 2" C24 timbers which will be hung from the steel beams.  Yup, you guessed it, the structural engineer strikes again!

The yellow tinged timbers are the C24 structural timbers specified by the structural engineer.  When assmbled these timbers will create thirteen 9" x 8" joists.  To put this in context, the first floor of my house is supported by single 8" x 2" joists spliced over a supporting wall, much in the way that the existing loft joists are.

This is the detail at the splice joint of the existing timbers.  The 9" x 2" extends the spliced joist 300mm past the line of where the steel beam will sit.  84mm high timbers will site on top of the existing joist to create a 9" x 4" sized joist.  The C24 timber will then sit either side of this and be coach bolted through at staggered centres to create a 9" x 8" sized joist.

This is the view from the other side of the joists

Loft Conversion - Steel yourself for this nonsense

Here are the steels which the structural engineer has insisted is the only way to support the additional en-suite bedroom in the loft space.  These are required in addition to the 'quadrupled' up 9"x2" joists and the flitch beam.

and here's a close up of the 6.8metre long x 254mm x 146mm x 43Kg universal beams which i need to crane into my loft to hang the 9"x2" C24 joists from.  They have a spliced joint at 2/3rd section and when bolted together each of these beams will weigh 300kg (47 stone).  In my opinion this is complete overkill and could have been avoided by the use of alternative glue-lam beams or other modern, timber composite alternatives to steel. So, here we are already £4k over budget.

This is the flitch beam which I had to construct to satisfy yet another requirement of the structural engineer.  The flitch beam comprises of a 6m long x 200mm high x 13mm thick steel plate sandwiched between two 220mm x 50mm C24 structural beams the same length. The flitch beam will sit at a 90 degree angle to the steel beam around the edge of the stairwell opening and will be suspended from the steel beam by anchor ties.

The assembly is held together by 130mm grade 8.8 x M12 bolts placed at 200mm staggered centres with single sided toothed connecters either side of the steel plate which bite into the timber.  I estimate that this weighs approximately 120Kg (19 stone) and because of the length and weight this will need to be craned straight into the loft along with the steel.

Structural engineer - bolt!

Loft Conversion - A corker of a time

I had always thought that laying loft insulation was the worst job in the world, turns out i was wrong, it's the 2nd worst job in the world.  The worst is removing loft insulation!

and just when you thought you'd prepared yourself for an evening of hot, sweaty, sticky action you lift the itchy, invasive glass wool to find dusty, loose, cork insulation which will need to be swept up.

The glass wool insulation was bagged up and disposed of at the local civic amenity site, the foil wrapped lengths of insulation were laid aside for reuse in the eaves area later.  The loose cork insulation was bagged up and set aside for re-use in the under-floor area, because a wee bit of t'internet research has confirmed that loose cork has insulation qualities which are at least equal to, possibly better than, glass mineral wool (c.0.045Wm/K).  Not only that, it's in short supply and accordingly is quite an expensive insulation option.

With the floorboards lifted, the route of the electrical conduit can be seen.  The conduit will be bypassed by the new wiring for the loft conversion and lighting in the ceiling below which will be installed by a qualified electrician to ensure compliance with current regulations.

With all the insulation removed, the 6"x2" joists and their spliced joints can be seen.  These joists will be doubled up and packed out in line with the structural engineers requirements prior to being sandwiched between the C24 timbers specified by the structural engineer.

Loft Conversion - Parging the Party

 To prevent any leakage of fumes from the 4 flues within the chimneybreast into the new room the brick chimneybreast party wall had to be coated with a mortar render.  The process of coating the wall with the mortar is known as parging.

Parging is a fairly easy and straighforward DIY job, particularly as the finished wall will be hidden behind an insulated and plasterboarded partition.  The most difficult bit of parging is carrying the many buckets of mixed mortar up into the loft (or alternatively, carrying all the bags of sand and cement and buckets of water up into the loft).

There was a small gap at the top of the brickwork between my neighbour's loft and mine (barely big enough to put a finger in).  This gap was filled with fire retardent expanding foam to reduce the risk of fire breaching the party wall in any direction.

Not a great picture, but that's the job done.  Yes, the chimneybreast is an odd shape, however it'll eventually be behind an insulated partition, so who cares!

Loft Conversion - A single step and all that

Right, the blog is now back online after quite a bit of time off.  Lots of the time off was spent preparing for the next project, which is probably the biggest project i've ever undertaken.  So, here goes, 2015/16 will be the year of the loft conversion and i'll keep the blog updated to show you the progress made and some of the technical stuff required along the way.

Fortunately the shape of the trusses already provided for the basic shape for the planned bedroom and en-suite and didn't require any alterations to the roof trusses other than the strengthening of the joists (more about that later) and the fitting of ridiculousy sized steel universal beams to carry the weight of the floor (i'll have a right good moan about that later).

As you can see, the children of the former owner(s) must have used this as a den/hangout at some point in the past.  By a strange coincidence i recognised one of the names and when i spoke to the woman she confirmed that she had stayed across the road from this house, had been friends with the girl who lived here and that they often hung out in the loft.

 This is the area between the collars and the ridge of the roof looking towards the party wall and chimneybreast which seperates my neighbour and I.

So, that's my loft in it's current state, but it won't stay that way for long!