The installation of a new furnace or reconditioning of an existing one might involve installing a vent in the home’s foundation, and the process might seem perplexing if the foundation is constructed of masonry or cinder blocks. It is not that difficult, though, especially in the event that you have access to high-resolution masonry cutting tools, which you can usually rent. It is possible to perform the work even with no tools, but it’s a bit more time-consuming.

A Masonry Saw for Rectangular Holes

Masonry saws look a little like oversized wood-cutting circular saws, however they employ diamond-edge grinding wheels as opposed to toothed blades and spray a jet of water while the saw is working. They are ideal for cutting rectangular holes. You typically make a first score with the blade thickness set to an inch or so, over-cutting the corners by several inches. You then progressively increase the cutting thickness as you make repeated passes to cut down the hole. The best-quality tools incorporate a track that attaches to the wall for security, stability and cutting precision.

A Core Drill for Round Holes

You may be installing a 4- or 6-inch span of circular pipe as part of the vent installation, and you can not cut that type of a hole with a saw. The ideal tool for this scenario is a core drill, which can be somewhat like a hole saw for timber except that the sword has a diamond grinding edge instead of tooth and the saw cuts deeper. Like a masonry saw, a core drill is water-cooled, and you ought to proceed slowly when using it. Cinder block is not as dense as masonry, though — and it can be hollow, even if it is not filled with concrete — so it doesn’t take long to generate a hole in it.

The Drill-and-Chisel Method

If you don’t have access to high-class cutting tools, then you can perform the job with a variable-speed hammer drill, a 1/2-inch masonry bit, a cold chisel and a hammer. The general process would be to trace the outline of this hole you need on one face of this wall, drill a series of 1/2-inch holes around the outline, then use the chisel to break the links between the holes so that you may get rid of the center. A couple of guidelines and tips will help you do so effectively without damaging your drill or cracking the wall.

Hole-Cutting Tips

Even though a hammer drill is generally suggested for masonry, you are likely better off with a conventional drill to get cinder blocks, that can be relatively soft and fragile. Space the holes about an inch apart while operating the drill at half speed or less to avoid overheating the little bit. It is a good idea to keep a bowl of water nearby in which to immerse the hint. Drill all the way through the block, then tap the links lightly with the chisel to break them. If you are making the hole via a hollow part of block, you might even see that a tap on the middle of this hole dislodges it. Always take appropriate precautions when using power tools. Wear safety glasses together with equipment to protect your hearing and mind.

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