Property:Development:Construction:Windows
Summary
Stuff has a decent summary article about windows that is ok as a starting point1).
Other Materials
- MOCHI (Mesoporous Optically Clear Heat Insulator (1% loss of transparency, minimal hazing)
- Transparent Wood: Developed in Sweden, this wood-based material is stronger than glass, offers better insulation, and is biodegradable. (10-20% loss of transparency).
- But does the polymer yellow in sunlight over decades?
Notes
* Windows are a combination of several different elements which are priced independently and combined to make up the overall cost:
- Framings
- Glazing
Rules
* http://www.legislation.govt.nz/regulation/public/1992/0150/latest/DLM162576.html#DLM164975
- Glazing in NZ must be Strengthened when:
- <800mm from floor.
>0.5m.sq.
- <800mm from seating along wall/window seat
- <2000mm from bathroom tub/shower/sink.
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Chats
Not SmartFit. Residential or thermal is 12% more. Low E is 20% more but glass which is 25% cost of window. Consider wood (frenchdoor co), best thermal values. Dual colour black/white different expansion rates. Think $1000 per linear meter for ballpark.
Terms
Low Emission Glass (low-e glass): a thin film that can be bonded (during manufacturer (hard coat) or applied afterwards (soft coat)) to the inside surface of windows to reflect heat inwards (but also reduces gains from free heat from the sun in winter).- When applied to single panes, can decrease heat loss by 25%, but not guaranteed as it can increase condensation on the pane, largely defeating the gain.
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Acoustic laminated glass: A composite of two or more layers of glass permanently bonded together with an interlayer of resin, provides noise protection. It also can be used as safety glass.Low iron glass: Clearer glass used for shower stalls and splashbacks, shop windows, and high-end houses.Tinted glass: pigment applied at production or later using lamination to make a composite pane. Use sparingly or it can make a house seem dark.Insulated Glazing Unit (IGU).: when two panes of glass are sealed together with argon/other inert gas in between. Note that each pane in an IGU can be one of many types of glass: standard, low-e, low-iron, or a tinted composite.poly(methyl methacrylate): see plexiglass.plexiglass: more shatter resistant, slightly more expensive than glass, and requires care in choosing cleaning products as some may leave scratch marks.Storm Windows: exterior or interior seasonal retrofit over single pane windows (often somewhat unsightly) that can decrease heat loss by 50%. Not much benefit if already using double-glazing, low-e glass, etc.Single hung windows: windows with a single movable bottom half that can be pushed up. Really hard/impossible to clean from inside.Double-hung windows: windows for both halves that can be move so that either the top or bottom can be moved. Depending on age/construction quality the sashes will get loose and cause drafts/humidity. It's also generally more expensive than a single-sash window…but so common that by shopping around between suppliers one may find one better than single-hung window4).Awning window: a horizontal clerestory window that opens out from the bottom, with a crank to stop it crashing back down. More expensive than basic double-sashes due to the crank.Casement window5): a window that is hinged on the side. Either cranked, or restrained via a bar. Offer more light than double-hung or single-hung windows. You pay more due to the size of glass, therefore weight, therefore necessary sturdiness.French Windows:6) More or less the same as casement but opens inwards.Bay windows: consists of a picture window in the middle is surrounded by two smaller windows, called flankers. Even more expensive…Garden windows: external mini-greenhouses, often used in kitchens. Similar to a mini bay window, with a skylight to boot. Avoid, due to eventual leaking.Sliding windows: No longer as common as other window styles. Think of it as a horizontal single hung or double hung window. It has its uses when opening outwards is not practical, such as out over a walkway. It's more expensive than other options.- Notation can be “XO” based (eg: where
OX-Ois the same as- <- -).
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Picture Windows: a type of fixed window, but with a smaller frame size. Instead of matching the sitelines of adjacent windows, the frame is reduced, smaller, to show more of the view7).Fixed Windows: Unable to open, their glass panes are mounted directly onto the frame, maximizing view as well as insulation. They are the least expensive type of window, saving on weather-stripping and the time it takes to assemble movable sashes. Their lack of ventilation makes them extremely energy efficient windows (although that causes the need for other windows or hvac solution to provide it) but not fire escape solutions.skylight windows: Can be fixed or vented (opens much like a casement window). Can be curb-mounted (needs a box frame built up and flashed on which to sit the window) or the more modern deck-mounted (newer, lower profile, where the flashing integrates with the roof's flashing)8).
Recommendations
- TBD
Options
- TBD
Considerations
- The larger the pane, the more expensive. So sliding doors start off cheaper than bi-fold doors, but can get more expensive than bifold as the size mounts up.
- In an aluminum sliding door, the frame is the thermally weak spot (!), as oppossed to the glass (but both suck, actually, when compared to an insulated wall).
- to reduce cost, stick to fixed windows, with a judicious use of both awning windows (maybe in the bathroom steam, although an extractor can do the same task, especially if placed above the shower where the most steam is produced) and casement windows for cross ventilation. I'd personally avoid using single-hung or double hung windows, as well as bay and garden windows. I'd also invest in a limited number of *fixed/non-vented skylights if the house's eaves are wider than 6m.
- In NZ, uPVC is considerably more expensive than Aluminum.
Costs
Specifications
- TBD
Suppliers
- PVC:
-
- R-Value: aweful @ 0.35 (that's including thermal gap!)
-
- European. German. Wood based. With alum siding.
Ideas
* Money saving design:20) Some good ideas worth considering.
* Garage doors as window:
Risks
Although uPVC is used for 60+% of Europe's weather, ensure you choose a product that has proven it's ability to stand up to NZ's harsh sunlight.
Regulations
- The NZ Building Code indicates that vertical glazing should have an ‘R Value’ of not less than R0.26.
- This can be achieved with wood framing + single pane of low-e glass (reaching R0.27), but should be avoided, and instead go for double-glazing (R0.37) 21). Double glazed standard glass within uPVC joinery can reach 0.3622). Using low-e glass, can reach R0.5323). Aluminum joinery and double-glazing can't reach as high: standard glass double glazing: R0.33, and when using low-e: R0.4324)
- Note the above numbers as compared to a standard insulated wall: R1.9 (6 times better than double-glazed windows, and even more of a difference if using SIP panels).
- Where installing double-glazing alters the weather-tight envelope of a house it may be classified as “restricted building work” and need to be done by a licensed building practitioner. DIYers can now do restricted building work unsupervised but they must file a statutory declaration with their local council. The declaration will be kept on council property records25).
Heat
It appears that the use of a glass-plastic-glass laminated composite glass within a double-glazed ICU would provide the best results26).
Joinery
Options
- APL31): Windows & Doors. APL supplies over half of the residential construction market in New Zealand with windows and doors through three brands of which is the parent company: Alltherm Window Systems32), First Windows and Doors33), Vantage Windows & Doors34). At which point, they all seem to sell the same ranges
- Ranges:
- Residential:
- Up to 2.1 in High wind zone.
- ThermalHEART
- APL Architectural Series:
- 2.7 height max
- Metro Series: suitable for high wind.
- 2.4 height max
- Smartwood composite range.
- Miro, Urbo, Icon and Elemental are our exclusive hardware ranges that have an integrated look with our joinery ranges.
- Altus Windows 35):
- Union of NALCO and Fletcher Aluminum.
- Ranges:
- Pacific Suite®,
- Pacific Residential: suitable for high wind zones, windows up to 2.4m.
- Atlantic Suite®,
- Smartfit®
- ALTI®: a composite wood and alum window.
- Oakley®,
- Dualglaze™,
- Weathertight™,
- 41Architectural®,
- AllSeasons™ : thermal break alum.
- Sovereign Series™
* Bradnams36)
Glass
Tools
- TBD
Resources
- Why windows often come unglazed: