Browse Forums Building Standards; Getting It Right! 1 Nov 15, 2010 11:15 am I live on the ground floor of a two-storey blocks of units in Sydney and I want to create an 800mm (width) x 1000mm (height) hatch in an internal wall between the kitchen and living room. I assume the wall is bearing some load so I plan to install a Universal Beam (UB) above the opening but I don't know how to calculate the load in order to determine the size of UB required. I do know that the wall is 140mm thick (in total - I haven't chipped away the plaster to find the width of the brickwork yet), sits between two exterior walls 2230mm from one and 4400mm from the other and that the ceiling is a reinforced concrete slab throughout. The opening would be positioned 900mm from a door opening and 740mm from the wall closure on the opposite side. I'm aware the the information is scant here but given that the opening I'm planing to make is relatively small, do I need to arrive at an exact load calculation to determine which size UB to use? It appears that the wall could just about accomodate the dimensions of a 250UB25: 248mm Height x 124mm Width (25.4kg/m). This seems huge for such a small opening so perhaps I can go with something smaller? Or perhaps it is simply impossible to determine without a site inspection? If the advice is that it's crazy to even consider this without a detailed load calculation (i.e. engaging a structural engineer) then I will make this my first move. I'm confident of carrying out the building work - It's this first (vital) step that I'm unsure about. Any thoughts greatly appreciated... Cheers, Stew Re: Wall Opening - Load Calculation Required? 2Nov 16, 2010 10:32 pm Straight from the engineering plans of my double storey, double brick home. 22. LINTELS FOR LOWER WALLS OF TWO STOREY SECTIONS TO BE:- OPENING LINTEL MIN END BEARING UP TO 1200mm 100 x 75 x 8.0 UA 150mm UP TO 1800mm 100 x 100 x 8.0 EA 200mm UP TO 2800mm 150 x 90 x 8.0 UA 250mm UP TO 3300mm 150 x 100 x 10.0 UA 250mm Please don't take this as applicable to your situation, I'm just posting this to let you know the general sizes and end bearing required for our house. Your place may be different, however what you describe is nothing extraordinary. The difficulty in cutting in openings is getting the opening knocked out and then getting the lintel in place with the required end bearing while holding everything up. I'm a carpenter and have done it many times but it is still not an easy job. Getting a good cut through the wall is a dirty job. If you aren't involved in construction it is probably a bit of a big job to try and cut your teeth on. Accessible Carpentry & Cabinets accessiblecarpentry@gmail.com accessiblecarpentry.com.au https://www.facebook.com/pages/Accessible-Carpentry-Cabinets/583314911709039 Re: Wall Opening - Load Calculation Required? 3Nov 17, 2010 11:32 am Thanks chippy, Of course, I realise that this isn't directly applicable to my situation but I think this is all useful background info. I was interested to hear your comments on knocking through the opening and wondered if I might be able to ask you a little more about this... I'm planning to support the area above the opening prior to knocking through by means of some needles and a few acrows. I'm hoping this will provide enough temporary support while I knock out the section for the RSJ and slide it into place. Is this how you've done this before? Cheers, Stew Hi, My home construction is complete, and the handover is scheduled next week. However the construction has been delayed and I have raised this to the builder. The… 0 5327 Yes you are correct, unless there are outside works which form part of the contract such as landscaping or driveways, and importantly, the work delayed is on the critical… 1 3528 Any structural alteration to your home requires building permit. Before you get it you will have to supply plans with structural assessment, you will also be removing… 2 4121 |