SmartInsulationCalculator

Pipe Insulation Calculator

Foam pipe sleeves come in fixed lengths sized to the pipe's outside diameter. Enter your run and this counts sleeves, fittings and cost.

Your project

Covers cuts, compression and odd bays. 10% is the usual default.

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Prices as of Oct 11, 2026, 4:41 AM UTC. Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon.com at the time of purchase will apply to the purchase of this product.

How this calculator works

  • Sleeve length = pipe run × (1 + waste %)
  • Sleeves = length ÷ 6 ft per piece
  • Fitting allowance = elbows and tees × 0.75 ft

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Frequently asked questions

Which pipes should I insulate first?

Hot water lines from the heater out (fastest payback), then any pipe running through an unheated crawlspace, garage or attic where freezing is possible.

Does pipe insulation stop pipes freezing?

It slows freezing dramatically but won't prevent it in a sustained deep freeze with no water movement. In very cold spots pair sleeves with heat tape.

Which pipes should I insulate?

Hot water lines first, especially the first few metres out of the heater, because that is where standby loss is greatest and where insulation pays back fastest. Cold lines in humid unconditioned space are worth doing for a different reason: they sweat, and the condensation drips onto whatever is below.

Will pipe insulation stop pipes freezing?

It slows freezing; it does not prevent it. Insulation reduces the rate at which a pipe loses heat, so a pipe with no flow and no heat source in sustained sub-freezing conditions will still freeze eventually. Where freezing is a genuine risk, heat trace cable under the insulation is the measure that actually prevents it.

What thickness of pipe insulation do I need?

It varies with pipe diameter and the temperature difference, and codes give minimums for hot water lines by pipe size. Thicker is not always better in tight spaces — sleeves that cannot close properly around a pipe leave a gap along their length, and a poorly closed thick sleeve underperforms a well-fitted thin one.

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Sleeve length to buy

66 ft

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