How to install plasterboard or ply to Strammit?

[hamish71]

Im after advice as to how to install either plasterboard or ply to my ceiling. The ceiling throughout the house is currently Strammit (compressed straw panels). Intend using battens to provide a small relief for new light wiring, and securing the panels to the battens.

However, how do I secure the battens to the Strammit? To further complicate matters, in some places there is a significant roof cavity above the strammit, and in others there is none.

[EricL]

Hello @hamish71

Thanks for sharing that question about hanging plasterboard on your ceiling. It's great that you've managed to identify the type of material you have on your ceiling. Your description of the Stramit board is spot on, it's a compressed fiberboard material held together with natural adhesives. It is capable of holding light objects such as small light fittings and batten lamp holders, but anything heavier is not recommended.

In this scenario, your idea of installing battens is the answer to mounting the panels to your ceiling. However, instead of just putting in single battens, I suggest building a batten frame and fixing it to the timber beams running across your ceiling. The batten frame will now be the fixing point for your panels and there'll be no need to hang anything onto the Stramit board.

Please keep us updated with your progress, we look forward to seeing the start of your ceiling installation project.

If you have any other questions we can help with, please let us know.

Eric

[hamish71]

Thanks Eric,

Given I want to lose as little ceiling height as possible, and leave the beams exposed, what dimension timer should I use for the batten frame. Too big and I lose height and the exposed beams will look a little silly. Too small and I fear they will sag under the load. Beams are about 1150 apart.

[EricL]

Hello @hamish71

I recommend using 70 x 35mm Framing MGP10 H2 Blue Pine L/M in combination with 38 x 17mm 2.7m Melamine Batten Natural Wood. I don't suggest anything smaller because as you mentioned if the frame is too light, it will sag under the load. Adding the general thickness of plasterboard which is 10mm, you will have a combined thickness of 35mm + 17mm + 10mm = 62mm. Depending on how tall the beams are, this measurement is what you'll have to take into consideration.

If you need further assistance, please let us know.

Eric

[natalier26]

Hello @EricL. I am still looking into a project similar to the one that the original poster included. We have a straw ceiling with beams that are about 4m across. There are only two beams, approximately 2-2.4m apart. I am a complete novice (apologies if I'm being dense), but I don't fully understand how you would propose to use the two sizes of timber in your reply to Hamish to build the frame. Why do they have a combined thickness? Do you attach them to each other when building the frame?  

[EricL]

Hello @natalier26 

My apologies if I was not specific with my answer in regards to the timber combination. However, after much consideration it might be possible to achieve the same result just by using the 70 x 35mm Framing MGP10 H2 Blue Pine L/M. But in your situation extra support may be needed due to the span between your beams. Your roof structure has been designed to carry a specific weight and withstand a certain amount of inclement weather. Adding extra timber spanning a large distance will add weight and stress to the structure which the original designer has not accounted for.  

In order to modify your ceiling safely, I suggest engaging the services of a draftsperson or engineer in regards to adding a timber frame to your roof so that you can attach plasterboard to it. It would be best to have it assessed first before making any modifications to the existing structure. In this manner the added framing will be done to code and will comply with existing building rules and regulations.  

If you have any other questions we can help with, please let us know.

Eric