Frequently Asked Questions
How much does it cost to build a structure?
Obviously, this will depend on the type and size of structure and, the local material and labour costs.
How strong is the block?
The strength of the finished block is determined by the mixture. The recommended mix is 2 level wheelbarrows of sand, 1 x 50kg bag of 42 MPa cement and 2 level wheelbarrows of chipped stone (Not larger than 13mm stone), gives a block of roughly 5,2 MPa strength. The required strength in most countries for a concrete block (Reference B-Block) is 3,5 MPa. The block can be strengthened to any level by simply adding more cement. The above mixture makes 28 large blocks.How will the plumbing and electrical installations work?
These are all simply fitted into the hollow cavities which are completely clean by virtue of the bonding process.
What approvals does it have?
Made to the recommended concrete mix at 4,8 MPa Stumbelbloc blocks conform to SABS requirements of more than 3,5 MPa. When built with SABS and NHBRC approved thin bed mortar, they can legally be used to build with in RSA. Stumbelbloc does have Agreement and NHBRC approval.
What are its thermal properties?
Because the block is wet cast, it is far more dense and compact than dry pressed block and is therefore superior in thermal and strength quality. The construction method using the bed mortar leaves the block cavities completely clean. Traditional blocks need standard mortar which tends to block the cavities. Of course, the cavities themselves may be filled with any form of insulation material.