Glass & Energy Efficiency

Built for Nova Scotia winters

Every Nova window is made in our Burnside plant with insulated glass from Robover featuring Guardian ClimaGuard 80/71 low-E coating.

Calculate your savings Find rebates

As low as0.93Triple glazed U-factor

As low as1.54Double glazed U-factor

As low as0.20Air leakage (L/s·m²)

Locally made inBurnsideDartmouth, Nova Scotia

Energy Savings Calculator

How much could new windows save you?

Tell us about the windows you have now and see an estimate of what they cost you to heat through a Nova Scotia winter, compared with ours.

1. Your current windows

2. How is your home heated?

3. Choose a replacement

Estimated yearly savings

$0

Current windows

$0

Our windows

$0

Heat lost through windows0%less

Electricity saved0kWh / year

Get a free quote

What's in our glass

Low-E glass made for cold climates

Our sealed glass units come from Robover, a Quebec insulated glass manufacturer with more than 20 years supplying the Canadian window industry. Our standard low-E coating is Guardian ClimaGuard 80/71, designed for northern climates, with a SWISSPACER warm-edge spacer on all non-shaped units. Other coatings are available if you need a different level of solar heat gain.

1

Lets the sun's heat in80/71 is a high solar gain coating, so winter sunlight still warms your rooms for free.

2

Keeps your heat insideThe invisible metal-oxide layer reflects heat from your furnace or heat pump back into the room.

3

Clear, bright viewsHigh visible light transmission means no tinted or mirrored look.

4

Warmer glass edgesSWISSPACER holds the panes apart with an insulating composite instead of aluminum, so the edge of the glass stays warmer and less prone to condensation.

OutsideInside

Glass pane ClimaGuard 80/71 low-E

Triple glazed unit shown, with low-E on the inner face of the outside pane and the outer face of the inside pane.

Compare

Double glazed vs triple glazed

Both are ENERGY STAR certified and a big step up from older windows. Here's how to choose.

ENERGY STAR

Nova Double Glazed

Great value and the most free solar heat.

1.63U-factor (W/m²·K)

36Energy Rating

0.56Solar heat gain

0.62Visible light

Lets in more winter sun, which helps south-facing rooms
Lighter sashes that are easy to open and close
Brightest view of the two options
Lower upfront cost

Best for: budget-conscious projects, sunny exposures, cottages and rentals.

ENERGY STAR Most Efficient

Nova Triple Glazed

The lowest heat loss and the warmest feel.

1.05U-factor (W/m²·K)

44Energy Rating

0.48Solar heat gain

0.56Visible light

About 35% less heat lost through the window than our double
Warmer inside glass, so less condensation and fewer cold drafts near windows
Quieter rooms thanks to the extra pane and air space
Recognised as ENERGY STAR Most Efficient by NRCan

Best for: year-round homes, north-facing rooms, bedrooms on busy streets and anyone heating with electric baseboards.

Ratings from NRCan listings NR6947-49252679-ES5 (double) and NR6947-49252693-ES5 (triple), Series 4200 single hung, vinyl frame.

Grids & energy ratings

Why grids lower the Energy Rating

Grids and simulated divided lites (SDL) look great, but they slightly lower a window's Energy Rating. The window doesn't lose more heat. It gains less free heat from the sun.

1

Bars block sunlightEvery grid bar covers a strip of glass, so less winter sun reaches your rooms. Solar heat gain on our triple glazed unit drops from 0.48 with no grids to 0.39 with 1" grids.

2

Wider bars block moreRatings are tested in two widths, under 1" and 1" or wider. The wider the bar, the more glass it covers and the bigger the drop.

3

Heat loss stays the sameThe U-factor doesn't change with grids. In a heating climate like ours the Energy Rating also credits free solar heat, so less sun means a lower score.

Still ENERGY STAR: every grid option on our triple glazed window remains ENERGY STAR certified. If you love the look, choose narrower bars or keep grids to the front of the house to limit the effect.

Nova Triple Glazed, single hung

OptionSolar heat gainER

No gridsSHGC 0.48 · light 56%

44

Under 1" barsSHGC 0.43 · light 50%

41

1" and widerSHGC 0.39 · light 44%

39

U-factor is 1.05 for every option. Grids between the glass and SDL bars rate the same at each width. From NRCan listings NR6947-49252693 to -97-ES5.

Reading the label

What the numbers mean

Every ENERGY STAR window has a label with these ratings. Here's how to read it when comparing quotes.

Lower is better

U-factor

How much heat escapes through the whole window. ENERGY STAR requires 1.22 or lower, or an Energy Rating of 34+.

Higher is better

Energy Rating (ER)

A Canadian score that balances heat loss, solar gain and air leakage into one number for heating climates.

Depends on the room

Solar heat gain (SHGC)

How much of the sun's heat comes through. Higher helps in winter; very large south-facing glass may run warm in summer.

Lower is better

Air leakage

How much air sneaks past the sash and frame, tested to CSA A440. All our operating windows test at 0.50 L/s·m² or lower.

Rebates

Get money back on new windows

Important: book your assessment before any work starts. Work done before the assessment does not qualify.

Check current rebates Financing options

Program details and amounts are set by Efficiency Nova Scotia and can change. Check their site for current eligibility.

1
Book a Home Energy AssessmentAn advisor visits and finds where your home is losing heat.
2
Get your free Nova estimateWe quote ENERGY STAR windows that match your assessment report.
3
We make and install themBuilt in Burnside, installed by our own crews.
4
Claim your rebateFollow Efficiency NS's steps to finish the program. We'll supply the product details you need.

Common questions

Is triple glazing worth it in Nova Scotia?

For most full-time homes, yes. Our long heating season means the lower heat loss adds up year after year, and the warmer inside pane makes rooms feel more comfortable. Try the calculator above with your own windows to see the difference.

Will low-E glass make my windows look tinted?

No. ClimaGuard 80/71 is a high-clarity coating designed to let in plenty of daylight and solar heat.

Why do my new windows get condensation?

It usually means your new windows are doing their job. New windows seal much tighter than the old ones, so less moisture escapes from cooking, showers and even breathing, and indoor humidity goes up. When that moist air touches the glass on a cold day, it condenses. It’s an indoor humidity issue, not a window defect. To reduce it, keep winter humidity around 30–40% (lower on very cold days), run your bathroom and kitchen fans or HRV, and open blinds and curtains so warm air reaches the glass. Condensation on the outside of the glass on cool mornings is also normal and is a sign the glass is insulating well. Moisture or fog between the panes is different: that points to a seal failure, which our insulated glass warranty covers.

How can I verify your ENERGY STAR ratings?

Search our NRCan reference numbers (NR6947-49252679-ES5 and NR6947-49252693-ES5) on Natural Resources Canada's searchable product list.

Can I get triple glazing in any window style?

Yes. Triple glazing is available in every operating style we make: casement, awning, single hung, double hung, single slider, double slider and tilt-turn.

Can I choose a different low-E coating?

Yes. ClimaGuard 80/71 is our standard because it suits Nova Scotia's heating season, but other coatings are available if you want less solar heat gain, for example on large south or west-facing windows. Ask your sales rep about options.

What warranty comes with the glass?

Our insulated glass units carry a lifetime warranty against manufacturing defects, including seal failure that causes dust or film between the panes, for original owners living in the home year-round. Cottages, cabins and rentals are covered for 10 years. See our warranty page for full terms.