Timber Spring Sash Windows.
The Balance Spiral/Spring sash window takes its roots from the original sash window but it’s designed to suit modern constructions. By using Spring/Spiral balances the sections of the frame can be slimmed which giving the aesthetic appearance once installed comparing to traditional sash window.
Detailed drawing (PDF – SPRING SASH WINDOW)
PRE-TENSIONED SPIRAL SASH BALANCES
The Caldwell range of spiral sash balances are designed for use in vertical sliding windows with a tilt-in-facility, together with serving hatches and counter screens. We use Caldwell pre -tensioned Torso & Ultralift balances for our spring sash windows.
For sash weights of 3kg to 50kg we recommend pre-tensioned Torso double sprung balances with very high reliability and excellent track record. Torso sash balances provide torque-free lift for over 50,000 cycles which is equivalent to over 100 years in normal use. Torso balances, which have 19mm PVC tubes, can be specified for traditional vertical sliding spring sash windows and tilt-in windows to offer 70% – 75% mechanical advantage.
Ultralift pre-tensioned balances are available for vertically sliding sashes weighing 6kg to 27kg. To provide the extra lift, Ultralift balances are double sprung, resulting in a 70% – 75% mechanical advantage. Ultralift balances that have 17mm diameter PVC tubes, can be specified for traditional vertical sliding spring sash windows and tilt-in windows.
All our spring sash windows are constructed from high quality timber such as:
PINE – a white / pale soft wood which is light weight and straight grained, it is the most popular wood that occurs in Europe, it is less dense than hardwood but resists shrinking and swelling extremely well
MERANTI – a hard wood that comes from Southeast Asia – low-lying rain forests in low mountainous regions , features with relatively good outdoor durability, it offers best option for hardwood comparing cost effectiveness
OAK – a hard wood that can be found in most countries of Europe, oak prefers dry areas rather than damp environments, having the best characteristic from all natural wood and giving the best durability
For constructing all our spring sash windows we use high performance double glazing units offering a wide range of glass patterns and spacer bars, our units are manufactured to the best standards……
Sash lifts (pulls) allow the sashes to be easily vertically opened and closed, we offer them in the variable range and finishes , the top sash is specified as standard with a sash eye – available in satin, chrome and brass finish.
Flich fastener (catch) – allow secure feature to the sash window – comes in different finishes : satin, chrome or brass.
Vent Lock / Sash restrictor (sash stops) – can replace flinch fasteners, offers better security for intruders, available in different finishes
Trickle Vents can be fitted in either the head of the sash or the frame – details available upon request.
Glazing bars, beadings and sash Horns.
Glazing bars and beadings are designed to specifications and project requirement . The most popular is astrogal bar which comes in different widths. Timber beadings comes as standard but can be manufactured to specific details.
The height of glazing bars depends on the double glaze unit thickness. When 24mm double glaze unit is fitted we have to install very thin bars around 12mm in height, reducing thickness of glass we can achieve better mouldings.
Decorative sash horns to inside sash can be a standard moulding or can be design to mach original ones.