Insulation & soundproofing

Rigid XPS type 4 (30+ psi) board 4 in 2x8 (R20)

2 retailers compared

BMR
Canac

Best price$55.26 to $58.58

Average price $56.92Prices observed on August 12, 2026

Save up to $3.32between the cheapest and the priciest retailer

Bâtir à Rabais cannot guarantee this price. Always confirm it in store: prices vary by store, quantity purchased and current discounts.

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In short: Rigid XPS type 4 (30+ psi) board 4 in 2x8 (R20) is compared across 2 Quebec retailers, from $55.26 to $58.58, averaging $56.92. The cheapest retailer changes week to week. Sign in for free to see the exact price at each retailer and spot the lowest.

Is this part of a bigger project?

One product is a single line. Across a full list, the gap between retailers adds up to hundreds of dollars.

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Savings tracked project by project.

Propriétaire $8.99/month · 15 comparisons a month, cancel any time. | Multi-project 14-day free trial · Then $199 a year, 50 comparisons a month.

Buying your Rigid XPS type 4 (30+ psi) board 4 in 2x8 (R20) the smart way

Rigid XPS type 4 (30+ psi) board 4 in 2x8 (R20) is a product we compare for you across several Quebec retailers. Insulation is chosen based on the target R-value and the surface to cover.

From one retailer to the next, the price of the same product can vary noticeably. The price follows the market, the season and the weekly flyers. Check the observation date shown above to know how recent the range is.

The best move is to compare before you buy. By looking at the price range, then the exact price at each retailer once you are signed in, you immediately see where the product is cheapest at the moment you are shopping.

What is Bâtir à Rabais?

Bâtir à Rabais compares the price of construction materials across 19 Quebec retailers. You look up a product, we show you the price range, and once you are signed in, the exact price at each retailer.

With a plan, you build your full project list and we calculate your cheapest buying plan, store by store. You know exactly what to buy, where, and how much you are saving.

It started as a project by two guys from here, Simon and Alexandre, to help Quebec self-builders and renovators keep more money in their pockets.

Price notice

Displayed prices come from publicly accessible information (retailer flyers, catalogues and websites) that we are entitled to gather, observed at a specific point in time (see the date). They are provided for information only and may have changed since. Bâtir à Rabais inc. sells no products and does not guarantee the accuracy, availability or final price, which vary by store, region, quantity purchased and current discounts. Always confirm the price in store before any purchase. Bâtir à Rabais inc. is not responsible for any price difference, error or stock shortage: only the in-store price prevails.

Frequently asked questions

How much does Rigid XPS type 4 (30+ psi) board 4 in 2x8 (R20) cost in Quebec?

The price varies by retailer and by week. The up-to-date range is shown above, and once you are signed in, you see the exact price at each of the compared retailers.

Which retailer is cheapest for this product?

It changes from one week to the next. Create a free account to see the price per retailer and spot the cheapest one at the moment you buy.

How does Bâtir à Rabais compare prices?

We gather the product price across our Quebec retailers and show you the range. With a free account you see the exact price at each retailer; with a Project Pass you get your full buying plan, store by store.

How do I choose the right R-value?

The target R-value depends on the part of the building (wall, roof, basement) and the applicable requirements. Pick the R-value and the surface to cover first, then compare the price per square foot for the same product at each retailer.

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