Stumbelbloc: beat the heat, one block at a time

  • Twelve times more thermally efficient than conventional brick cavity walling, Stumbelbloc’s new fireproof building block has many applications. Image credit: Sean Woods
  • A unique patented interlocking block profile makes accurate building easier. Image credit: Sean Woods
  • Like grown-up Lego blocks, they help make building a more accurate process. Image credit: Sean Woods
Date:24 August 2017 Author: Sean Woods Tags:, ,

Stumbelbloc is a locally developed fireproof building block keeps the heat out along with the cold.

Hot or cold, it doesn’t matter what end of the heat spectrum you’re coming from: too much of either can be a bad thing. That said, keeping our homes within the habitable “goldilocks zone” during our hot summers has become a financial burden. For many South Africans and it’s only going to get worse. It’s a double whammy, because as global warming pushes temperatures up, so our electricity tariffs escalate. It’s the worst nightmare for any lover of air conditioning.

An affordable DIY building block?

You probably haven’t got a fancy off-grid home. But that doesn’t mean you can’t make your dwelling more thermally efficient. You’ll even save some hard-earned cash. Like spending it on Stumbelbloc’s affordable DIY building block, which is so thermally efficient it boasts a 60-minute fireproof rating.

The block can keep out cold just as effectively as it does heat. It provides homeowners, farmers and companies renovating buildings with an affordable building solution. It also also allows them to cut down on future heating and cooling costs.

Stumbelbloc’s Andre Esterhuizen explains: “As our fireproof blocks are 12 times more thermally efficient than conventional cavity brick walling, they have many applications: from resisting intense flames for an hour to keeping homes and stored perishable items cool when it’s blistering hot outside. Being such great insulators, they also work the other way around, efficiently trapping heat inside during winter, too.”

Each block weighs 6 kg (or about one-third the weight of a normal concrete block). Using them to build costs about the same as erecting drywall.

Stumbelbloc’s fireproof blocks

Like Stumbelbloc’s standard building blocks, the fireproof blocks feature the company’s same unique patented interlocking profiles. Like grown-up Lego blocks, they help make building a more accurate process and can be made onsite using plastic moulds or purchased ready-made.

When perfecting his top-secret fireproof perlite mix, Esterhuizen couldn’t make the blocks load-bearing. But, as an experienced builder, he doesn’t see this as a problem and wouldn’t hesitate to construct an entire home out of them. “I would just put in concrete support columns and use the blocks for shuttering, then fill all the blocks under trusses with concrete.”

All Stumbelbloc variants is bonded together using Blockgrip, instead of mortar. It sets in three hours, and is applied by simply dipping their bases into the mix. This makes the construction process at least 10 times quicker, less messy and significantly cheaper than conventional methods. Less than one barrowload of waste is gathered during a typical day of construction.

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