Question 1

What is the cost difference between insulating a poured concrete foundation with interior versus exterior rigid foam in a Saint John NB home?

Accepted Answer

Interior rigid foam insulation costs approximately $2,500-$5,500 for a typical Saint John basement, while exterior foundation insulation runs $8,000-$15,000+ for the same space — making interior application roughly 60-70% less expensive upfront, though exterior insulation provides superior long-term performance.

The cost difference stems primarily from excavation and waterproofing requirements. Interior basement wall insulation involves applying 2-3 inches of XPS rigid foam directly to the foun

Question 2

What is the recommended insulation strategy for the foundation walls of a New Brunswick ICF (insulated concrete form) new build?

Accepted Answer

ICF construction already provides excellent foundation wall insulation — typically R-22 to R-25 — that meets or exceeds New Brunswick Building Code requirements for below-grade walls (R-17 to R-20). The integrated foam insulation in ICF forms eliminates thermal bridging and creates a continuous insulation layer that conventional poured concrete foundations cannot match.

Understanding ICF Foundation Performance

ICF blocks consist of expanded polystyrene (EPS) foam forms that remain in place aft

Question 3

What are common mistakes when insulating a New Brunswick basement? | Insulation IQ?

Accepted Answer

Basement insulation mistakes in New Brunswick are expensive because they tend to be hidden behind drywall for years before they surface as mould, musty odours, or unexpectedly high heating bills. Climate zone 6 is unforgiving — the combination of cold winters, deep frost penetration, and humid shoulder seasons means errors in moisture management and thermal performance compound over time. Here are the most common mistakes NB homeowners and contractors make when tackling this project.

Insulating

Question 4

How deep should exterior foundation insulation go below grade in NB? | Insulation IQ?

Accepted Answer

Exterior foundation insulation depth is one of those details that separates a properly insulated New Brunswick home from one that loses heat steadily through the slab and lower walls all winter long. The short answer is that insulation should extend down to the bottom of the footing — but the reasoning behind that target, and the practical trade-offs involved, are worth understanding before you start digging.

The NBC 2015 (National Building Code as adopted in New Brunswick) and provincial energ

Question 5

How do I insulate a block foundation wall in a Campbellton home? | Insulation IQ?

Accepted Answer

Block foundation walls — typically concrete masonry units (CMU) — present a specific set of challenges that poured concrete walls do not. Campbellton, situated in northern New Brunswick and well into climate zone 6, experiences some of the harshest winters in the province, making a well-executed block foundation insulation project genuinely important for both comfort and energy costs.

The core problem with CMU walls is that the hollow cores in the blocks create air pathways that can move cold a

Question 6

Should I seal my basement walls before insulating in New Brunswick? | Insulation IQ?

Accepted Answer

Sealing basement walls before insulating is not just recommended in New Brunswick — for many homes, it is the most important step in the entire process. Skipping it can trap moisture inside your insulation assembly, creating conditions for mould growth, reduced thermal performance, and structural deterioration over time. Given NB's climate zone 6 winters and the wide variation in soil conditions from Moncton's sandy coastal plain to Saint John's granite and clay mix, the appropriate sealing stra

Question 7

Can I insulate a walkout basement differently than a full basement in NB? | Insulation IQ?

Accepted Answer

Yes — a walkout basement has a fundamentally different exposure profile than a fully buried basement, and the insulation strategy should reflect that. Understanding the distinction helps you spend your insulation budget wisely while meeting the requirements of New Brunswick's climate zone 6.

In a full basement, the foundation walls are almost entirely below grade. The surrounding soil provides meaningful thermal mass and some protection from extreme cold, even if it does not actually insulate t

Question 8

Does insulating a basement floor help with comfort in NB winters? | Insulation IQ?

Accepted Answer

Yes, insulating a basement floor makes a meaningful and often surprising difference in comfort during New Brunswick winters — though the mechanism and the appropriate method depend on how you use the space and what's currently under your feet.

Why basement floors are so cold in NB. Basement floors in New Brunswick sit directly on or just above a concrete slab, which is itself in direct contact with the earth. Ground temperatures below the frost line in NB hover around 7–10°C year-round, but the

Question 9

What is the best way to insulate around basement windows in Rothesay NB? | Insulation IQ?

Accepted Answer

Basement windows are one of the most overlooked weak points in a home's thermal envelope, and in Rothesay — where winter temperatures can easily plunge to -20°C or colder — a poorly insulated window frame can create a noticeable cold draft and significant heat loss. Getting this detail right takes careful attention to the rough framing, the gap between the window frame and the foundation wall, and the transition zone where interior insulation meets the window buck.

The first step is to assess t

Question 10

Should I insulate the floor above an unheated crawl space in Dieppe? | Insulation IQ?

Accepted Answer

Yes — insulating the floor above an unheated crawl space is one of the most impactful upgrades you can make to a Dieppe home, and it's a project where the return on investment is felt immediately every winter. Dieppe sits in Westmorland County, in the Greater Moncton area, where January average lows hover around -14°C to -16°C. An uninsulated floor above an unheated crawl space is essentially a giant cold radiator pulling heat out of your living area, making hardwood floors feel frigid, inflatin

Question 11

How do I insulate a basement header and rim joist area in New Brunswick? | Insulation IQ?

Accepted Answer

The rim joist and header area is one of the most overlooked but highest-impact insulation targets in any New Brunswick home. Positioned at the very top of the foundation wall — where the floor framing meets the concrete or block — this zone is exposed to outdoor temperatures on three sides: the exterior wall, the cold slab or crawl space below, and often inadequate insulation above. In a typical older Fredericton, Moncton, or Saint John home, the rim joist can account for 15–25% of total basemen

Question 12

Is spray foam or rigid foam better for NB basement walls? | Insulation IQ?

Accepted Answer

Both spray foam and rigid foam board are legitimate approaches to insulating basement walls in New Brunswick, but the right choice depends on your wall configuration, budget, and tolerance for DIY complexity. Understanding the strengths of each material — and how New Brunswick's cold, damp climate shapes that comparison — will help you make the best decision for your home.

Spray foam (either open-cell or closed-cell) adheres directly to poured concrete or block walls, sealing every crack, penet

Question 13

Can I insulate my crawl space myself or do I need a contractor in NB? | Insulation IQ?

Accepted Answer

Crawl space insulation is one of those projects where the honest answer depends heavily on your crawl space's specific conditions, your comfort with confined-space work, and which insulation method you choose. Some approaches are genuinely DIY-accessible; others involve materials or code requirements that make professional installation the safer and smarter path.

First, understand what you're dealing with. New Brunswick crawl spaces fall into two general categories: vented and unvented (conditi

Question 14

What R-value does NB code require for basement wall insulation? | Insulation IQ?

Accepted Answer

New Brunswick follows the National Building Code of Canada (NBC) 2020, which the province adopted with its own amendments. Under the NBC 2020 for Climate Zone 6 — which covers all of New Brunswick — the minimum effective thermal resistance required for below-grade foundation walls is RSI 3.0, which translates to approximately R-17 in imperial units. This is the baseline that new construction must meet.

It's worth being precise about what "effective" means here, because it matters in practice. E

Question 15

How do I insulate a fieldstone foundation in an older Saint John home? | Insulation IQ?

Accepted Answer

Fieldstone foundations are common in older homes throughout Saint John, Fredericton, and rural New Brunswick — particularly in houses built before the 1930s. They are also one of the most challenging insulation scenarios a homeowner can face, because fieldstone is fundamentally different from poured concrete or concrete block in both its thermal behaviour and its moisture dynamics. Getting the insulation right on a fieldstone foundation requires respecting how these walls work rather than fighti

Question 16

How much does it cost to insulate a basement in Moncton NB? | Insulation IQ?

Accepted Answer

Basement insulation costs in Moncton — and across New Brunswick generally — vary considerably depending on the method used, the size of the basement, its current condition, and whether you're insulating walls only, floors, or a combination. Here's a realistic breakdown of what homeowners are paying in 2025–2026.

For interior basement wall insulation using rigid foam and batt, which is the most common retrofit approach, expect to pay $3,500–$8,000 for a typical 1,000–1,200 sq ft ranch or bungalo

Question 17

Can I insulate a damp basement in New Brunswick without causing mould? | Insulation IQ?

Accepted Answer

The short answer is yes — but only if you address the moisture source first and choose the right insulation system. Insulating a damp basement with the wrong materials or in the wrong sequence is one of the most reliable ways to create serious mould and rot problems in a New Brunswick home. The good news is that with the correct approach, insulation can actually be part of the moisture management strategy, not a liability.

The first principle is non-negotiable: fix the water before you insulate

Question 18

How do I insulate a poured concrete foundation in Fredericton NB? | Insulation IQ?

Accepted Answer

Poured concrete foundations are extremely common in Fredericton-area homes, particularly in properties built from the 1960s through the 1990s. Insulating them properly requires understanding the thermal and moisture dynamics at play, because a concrete foundation wall in Fredericton behaves very differently from above-grade walls — and the consequences of getting moisture management wrong in a concrete foundation are more severe than in almost any other part of the building envelope.

Poured con

Question 19

Should I insulate my basement walls from the inside or outside in NB? | Insulation IQ?

Accepted Answer

This is one of the most common questions New Brunswick homeowners face when planning a basement upgrade, and the honest answer depends on your specific situation — but for most existing homes in NB, interior insulation is the practical choice, while exterior insulation offers superior performance when it's feasible.

Interior basement wall insulation is by far the more common approach in New Brunswick because it doesn't require excavating around your foundation. It's typically done using either

Question 20

What is the best insulation for a New Brunswick basement? | Insulation IQ?

Accepted Answer

New Brunswick basements present a specific set of challenges that make insulation selection more nuanced than it is for above-grade walls or attics. The combination of Climate Zone 6 winters, high groundwater in many areas of the province, the prevalence of older poured concrete and concrete block foundations, and the critical role of moisture management all factor into which insulation approach performs best and lasts longest.

The most important principle in NB basement insulation is this: the

Basement & Foundation