Browse Forums Building Standards; Getting It Right! 1 Sep 21, 2015 11:14 pm Hi there, Does anyone know if you can use normal plasterboard (not fire proof or water proof) for external ceiling under alfresco and porch? Our builder says they only use normal plaster and if we want them to use anything else it will cost extra. Apparently the area is too big to use fibre cement sheeting, at least that's what they told me. We are also in BAL 12.5 bush fire area and have already added BAL 12.5 bushfire requirement in our quote which include a heap of extras such as sarking to roof etc... but it doesn't mention anything about the plaster board ceiling. Doesn't it have to be at least water proof for outside use? Wouldn't you get mould otherwise? Sounds strange to me... Re: Plasterboard ceiling for alfresco and porch? 2Sep 22, 2015 6:38 pm I have had countless customers come in asking for paint for exterior plasterboard for this exact scenario. Very common. To protect it, you must use a self priming exterior matt acrylic. I would recommend Dulux Weathershield Matt for this. http://www.dulux.com.au/specifier/produ ... oduct=2264 This meets international water vapour transmission standards. Re: Plasterboard ceiling for alfresco and porch? 3Sep 28, 2015 10:19 pm Hi montereyQ1, I believe that plasterboard is not suitable for use in eaves, carports and the like. I suggest you ring the technical department of a plasterboard manufacturer, Boral is one. As to use of wet area type it is the jointing that will fail, I have been told by Technical advisors. I have seen many failures of plasterboard in garages! Cheers Leonardo_23 Re: Plasterboard ceiling for alfresco and porch? 4Sep 30, 2015 11:07 pm Exterior Ceilings Gyprock™ plasterboard is suitable for lining ceilings of carports, verandahs, alfresco dining areas, eaves or areas that are horizontal or incline downwards away from the building, provided the ceiling is protected from direct exposure to rain. In these applications: • Ceilings must be installed after the roof cladding has been completed and sealed. • Effective cross-ventilation for all spaces between the roof and the ceiling is to be provided. • Where high fronted eaves gutters are installed, care should be taken to ensure that water will not flow back onto the ceiling. • External ceilings are subject to wind loads and the ceiling framing in these cases should be designed to suit. Refer to AS1684 or the appropriate framing manufacturer for more information. Plasterboard installation details are suitable for wind classification N1 and N2 to AS4055. • Plasterboard to be fixed using screws or nails only. • Back-block all plasterboard joints. • Plasterboard and cornice must be finished with an external grade paint system. Apply a good quality wallboard sealer and two coats of external grade paint to paint manufacturer’s recommendations. • In highly corrosive environments such as coastal areas or in applications were corrosion is of concern, the Rondo E-beads should be used in place of metal casing beads. Thank you alexp79 and gommeqld for your advice, that's very helpful, thanks 3 7934 What we have done in a few theatres ( including my own) is run 2 layers of 13mm gyprock, but sounds insulation especially for the bass is really tricky as a lot of that… 4 2553 Plasterboard Gyprock is very popular as a reveal liner these days. You need to provide a way of supporting it, we use a modified timber reveal or bracket. You will be… 1 4743 |