DavidYu

Hi all, I’m planning a loft conversion and would really appreciate some practical input from those who’ve dealt with steel replacement and logistics. My structural engineer has confirmed that both of the options below are structurally acceptable, but I’m keen to understand which is likely to be more straightforward and lower-risk to execute on my site with restrictive access and a nearby tree. Option A Replace the existing steel beam above the ground-floor kitchen/utility with a larger beam that can support the additional load from the new cut-timber loft structure (see below). Option B Install two new ~6.3m 203 UC steel beams at second-floor level on either side of the stairwell, to keep the load central and avoid the need to replace the beam in the kitchen/utility. Site constraints Access to the site is restricted. The only access is via a circa 2.7 m wide driveway running alongside a retaining wall. There is also a large pine tree at the front of the house, which limits lifting options. Steel is required in any event for the planned rear single-storey extension, so I’m therefore weighing up whether it’s generally more straightforward in practice to: expose and replace an existing internal beam at ground floor ceiling over 2 rooms, or manoeuvre and lift two 6.3m 203 UC beams up to loft level given the access and tree constraints. I’d be very grateful for any insights based on real-world experience.