Spring Balance Sash Window

Spring balance sash box window is a modern alternative to the traditional and immortal sash box window with lead weights, cords and pulleys, which has been around for centuries. A spring sash balance (or a spiral balance) is a pre-tensioned, spring-loaded device used in order to counter-balance an individual sash in a box sash window frame. Such sash balances eliminate the need for sash weights, sash cords and pulleys. As a result, there is no need for a bulky box-section-frame to both sides to hide from view any weights, etc. The in-build reveal in the window opening is therefore made redundant. Slimmer sightlines also mean that the glass area automatically becomes larger, letting more natural light into the building. That is exactly why the sash spring balanced window offers a more economical solution in comparison with its predecessor. It is often used in new build, because an architect would specify flush reveals. Also developers regularly incorporate spring sash windows where the costs need to be competitive but the end result still needs to be historically accurate and look great. Our spring sash window offers specification that ensures that aesthetic, thermal and acoustic requirements for properties are achieved. There are also some variations available. In addition to the usual spring sash window, there is now a new and innovated type, where the springs are covered. In this design, the spring balances on both sides are hidden from view to maintain authentic style of the traditional sash box window. Besides, such solution allows the new sliding sash window to be more in line with the old-style unbeatable aesthetics.

Our flagship product combines authentic style with precision engineering. Our sliding sashes are ideal replacement sash windows if you want to retain your house’s historic charm without windows that rattle or jam.

Using classic design and solid craftsmanship, our manufacturers creates bespoke vertical sliding windows to match the original design in order to retain the period character of your house. Each window is made to fit the original opening exactly, to provide a timeless elegance and sophisticated finish.

Unique draught-proofing in our windows overcomes the old problem of cold draughts associated with sliding sashes, thus maximizing heat retention.
Optional secure and safe ventilation locking as also Secured by Design fasteners are also available on request to our traditional windows.

About Angel Ventlock

Standard Specification

  • High quality spring balances from Caldwell Hardware Ltd.
  • Timber: Softwood (European Redwood) with a hardwood sill as standard.
  • Other hardwood options available: European Oak or Red Meranti from Malesia.
  • Only engineered (laminated) wood used to advance the quality, durability & performance.
  • Timber harvested only in sustainable and certified forests.
  • Fully factory finished with 3 microporous coatings applied on an anti-rotting & anti-fungi primer.
  • Spray-painted with Remmers typically to RAL 9003 or to client’s specification.
  • Any colour from the RAL Palette is available with us.
  • Alternative options available on request, such as: acoustic upgrade, solar-reflective & solar-control glass.
  • Double glazing:  standard, safety or double-safety glass depending on the requirements to meet Part L document.
  • Sample glass spec – Standard: 4mm/16 Argon/4mm Low E with Warm Edge Spacer Bar. U-Value 1.0 W/m²K
  • Achieving excellent U-Value for the whole window, much lower than the standard of 1.6W/m²K required by law.
  • Internally glazed in order to provide a secure anti-burglar solution & easier maintenance.
  • Timber parting beads.
  • Elegant glazing/Georgian bars.
  • Possibility of leaded lights in different configurations.
  • Optional: sets of architraves & window boards.
  • Secured by Design lockable heritage Fitch sash fastener.
  • Ironmongery available in 3 basic colours: Polished Chrome, Satin & Brass.
  • Optional restrictors: Angel Ventlock, traditional secure stop bolts and more.
  • Fully weather-stripped – 3 different types of seals.
  • Optional, but required by law for new build: trickle vents.
  • Excellent thermal and acoustic performance.
  • CE marked.

We are experts in manufacturing, supplying and installing traditional English windows on the UK’s market. We can offer you a free of charge, non-obligatory survey and detailed quotation within hours after that. We are famous for providing an excellent standard of service. All our projects have GGFi insurance covers and are FENSA certified.

This is how we would describe the main benefits from having our premium sash windows:

  • In the current economic climate of austerity following the 2008 crisis, everyone looks for ways to save money or to invest wisely. Wood is a naturally insulating material. It means that our timber windows help to retain heat within your home, which will in turn lower your household carbon emissions, keep your home wonderfully warm and reduce your fuel bills.
  • You can be the proud owner or a more attractive and stylish home thanks to the timeless beauty of our timber windows. Also, properties with timber windows always secure a better value on the market.
  • You are going to be more environmentally friendly. Wood as a natural material is automatically more eco-friendly than manmade options such as metal or uPVC. Especially if the wood is sustainably sourced, as is ours, meaning that the trees are being replanted to replace the ones which were cut down to make new windows.
  • If properly maintained, timber windows can last a lifetime and very well resist wear and tear. It is not unknown to see around the 150-years-old sash windows! Your wisely spent money will benefit generations to come.
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