The main reason a trussed roof is harder to convert is because each of the structural timbers are essentially in place to hold up the roof.
How to convert a trussed roof loft.
Removal and rebuild of roof.
Use a chalk line to draw a line along the floor parallel to the lower edge of the roof from one end of the attic to the other on both sides.
Often the height of the roof may be too low when constructed with truss rafters which means that it may need to be raised too.
A truss frame will occupy the majority of the space within the loft which means that the whole structure needs replacing if you decide to convert your attic.
This process involves the installation and use of steel beams.
In addition the design means the trusses occupy majority of the space within the loft therefore the whole structure will need strengthening if you decide to convert your loft.
Attic conversions are now possible by replacing the truss rafters with a shaped trusses or horizontal beams which in return create additional space.
The conversion from a trussed roof to a trussless roof simply involves the redistribution of the roofs weight from the trusses to beams running from gable to gable.
I have this above my own garage.
Measure the width of your roof trusses from inside to inside.
Room in roof trusses can be craned into place to form the shell of a ready made new loft room with the insulation placed above the rafters for maximum thermal efficiency.
The beams are supported by the gable ends of the roof and replace the original wooden struts which are removed once the steel beams are in place.
Look at this photo of the space created by attic trusses at my home.
The role of the horizontal beam is to tie the truss together and carry the load that would otherwise be sustained by the support and vertical timber also known as the king post.
Remove the existing roof structure and replace it with a larger one.
Attic trusses have a rectangular shape inside each truss.
The usual way in which trussed loft conversions are carried out is to install steel joists across the width of the roof and running the full length of the roof.
If the roof slope is steeper than 9 inches in 12 inches of run it doesn t take much width to end up with a nice room 12 feet wide with an 8 foot ceiling.