Structural calculations is our area of expertise. We ensure that structural issues do not get in the way of what you want. Many grand designs are structurally intensive like vaulted ceilings, large open rooms, balconies and loft conversions.

The types of renovation that will require Structural Calculations include:

1. Loft Conversions
2. Detached Garages
3. Listed Buildings
4. Staircases

Steel Support Beams

We design a considerable amount of steel beams for new openings formed within load bearing walls for new kitchen alterations, forming one room from two smaller ones and gaining access into new extensions. However, if it is necessary to remove more wall than is permitted by the Building Regulations, a portal frame is required to replace the stability lost as a result of removing the wall. This acts a "goal post" which transmits the wind loads safely to the ground.

Masonry is best suited to building with many internal walls. When large rooms are required masonry walls struggle to transfer wind loads to the ground. In the image opposite, we extended a gym with a dance studio over an open access to a car park. We designed and detailed the steel frame from an accurate measured survey lining up with the existing wall plates to keep the matching soffit lines. The building was also located on the boundary, the neighbours would not allow projecting pad foundations, so we designed a reinforced continuous beam foundation to get over this.

Steel Staircases

Steel staircases are often overlooked as structural members, but this is not the case. The staircase effectively is 2 beams in the form of stringers supporting the treads. If the stringers are not stiff enough, it gives the impression to the user that the staircase is not safe. If the treads are not strong enough they will deform and allow ice to form in the winter. The steel posts require foundations like any other structural member so the staircase should be suitably protected against the elements.

Loft Conversions

Loft conversions are becoming more popular as they can provide the additional space that is required and retain valuable garden space. Loft conversions are one of our specialities combining both our design and structural skills.

Loft Conversions come in all shapes and sizes and this one only comes in size. If accommodation is the only issue then large flat roof rear dormers are the easiest way to achieve this. In many situations this type of development does not need planning permission if the roof extension does not exceed 50m3. However, in this case Planning Permission was required as a result of the ground floor extension and the loft exceeding the permitted total of 70m3 for a semi-detached house.

Loft conversions require additional work to be carried out to the existing ground and first floor to help reduce the risk the risk of being trapped on the new floor in the event of a fire. These include:

• New internal fire doors and a protected route from the new 2nd floor
• Mains operated and interlinked smoke detectors on all floors

This is a section through a much simpler loft conversion where only roof lights are provided for light and ventilation. The staircase is key to any loft conversion, but it becomes critical where no dormer windows are provided to give additional headroom. The only headroom requirements within the Building Regulations relate to staircases and although there is a relaxation of the standard 2m minimum it can creates problems in this type of conversion. As a general rule the staircase can only be located in one of two positions, either over the existing staircase or between bedrooms "pinching" a bit of space of each. The structure on these conversions is simple, a new floor and the existing roof being supported on two steel beams between the existing gable and party walls.

Click here to view Loft Conversion Projects in our Portfolio