Our Services
Steel beams and frames
We design a considerable amount of steel beams for new openings formed within load bearing walls for 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.
Steel and spliced steel beams
Steel beams are used in many situations and loft conversions is one of many. This work was the regularisation of an illegal loft conversion where most of the roof had to be demolished and rebuilt. Generally most beams in loft conversions need to be spliced unless there is crane access and even then the splice will enable the beam to be inserted much easier. The splice is designed to resist the tension and compression in the bottom and top flanges respectively and the shear within the web. All of these calculations are carried out with "state of the art" software.
Steel feature frame using SHS or box section
A conversion of the roof space within this old listed stable block in Saffron Walden required a feature window located within the gable. A ridge beam was required to prevent spread of the roof as the floor level was dropped to provide the headroom for the new floor. Therefore a steel frame was designed to support the ridge beam and preserve the feature brickwork of the verge which was part of the conditions of the Planning Approval.
Portal Frames and Box or Picture Portal Frames
When the whole or a substantial part of an external wall is being removed there is more to consider than just the vertical dead and imposed loads. Traditional masonry construction are cross wall or shear wall construction and it relies on masonry being able to transmit wind loads in all directions safely to the ground. Approved Document A deals with this by limiting the amount of external or buttressing wall that can be removed and insisting that the corners or returns of these walls are substantial. The guidance states that no more than 66% of an external or buttressing wall can be removed and that a min of a 550mm (665 external) return is maintained. If this guidance can't be achieved a portal or box frame is required. This project located in Fleet, Hampshire needed a box frame as pad foundations would encroach onto the neighbours property.
