@Rongla,

Any key learnings for on the trappers? Buy or hire, timber or steel.
Noted you had over 1600 Square meters of slab. (4slabs of 400SqM)

I have seen some construction sites using trappers that look like block boards with a smooth finish. What are they? Are they cheaper than using say 9by1 or 8by1 timber for the trappers?

My fundi insisted on wooden trappers (without laying polythene) since they produce a rough finish which makes plastering the ceiling easier. He said they would have had to chip/roughen the surface - if we had used polythene on the timber or used metal tappers - to enable plastering to stick on that smooth surface.

@Tito, they are called marine boards, abit expensive and wear fast as well. They are best when used with polythene as base so they don't soak much water.

I am planning to put up a four storey apartment building. Have been thinking on ways to save costs. Has anyone considered using metal sheets as shutter for the slabs then re use it for doing the doors and gate. One can also use 4x2 and 3x2 cypress timber for the formwork support then re use these for door frames, roofing and wardrobes. Any thoughts on this? Pros, cons?