Sash Spring Balance Concealed in Stile

[Mmark]

I'm looking into https://balancesystems.co as recommended here before. However I'm struggling to find any real information on the web, beyond what the manufacturer provides

The system seems perfect, completely hidden spring balances, that provide full movement. And yet almost no window manufacturers uses this, and this sets of some alarm bells.

I went to one firm that can supply them, but they warned me that the systems cannot be balanced onsite. This can can cause problems, if they are not balanced perfectly. I'm wondering how serious that is, and is this why not more window companies offer this?

I looked at other concealed places, like Mumford or Patchet - which are more like semi concealed and I believe do not provide full movement. I still need to look into Westbury.

balancesystems.co seems great, but I would feel more confident if I could see more companies promoting and talking positively about this product.

 

[foxhole]

They are balanced at manufacture and don't need to be perfect , just work within tolerance.

 

[JohnD]

They appear to be a rebrand of the Amesbury type of spring balance, popular for many years in US and occasionally seen in UK. They are not at all novel. Availability is erratic. There is a kit to assemble them from parts, and it is sometimes easier to order a batch from a US supplier that holds good stocks.

The ones I have seen have the weight (in pounds) of the sash they are intended to support stamped on them, and you order them by length, sash weight and type of cap on the ends. If you know the size and weight of your sashes I see no reason you would want to adjust them. There is some friction in the movement so the sashes do not fly up and down if they are a bit lighter or heavier than the balance is rated.

The nylon cords will eventually wear and break. IMO the springs suffer rust weakening and also break, but I am in a coastal area with salt spray in storms. By the time they fail the pulley pivots are probably worn and noisy so not worth repairing unless replacements are unavailable.

They are quite easy to fit and remove when you know how, you can give them an occasional wash and spray with WD40 or something, to encourage silent and free running.

I notice the company you link is too bashful to show prices.

 

[Mmark]

The prices were very reasonable. He did tell me over the phone, but I forget what it was exactly. But it was only a little more expensive than normal spirals and less costly than weights and pulleys. Either way the pricing wasn't a concern for me, I wanted the best thing for the job. He said they typically resupply to manufacturers, than sell to individuals - which is why the website is not setup for end consumers. I wouldn't be buying the part, but going through a manufacturer who offers this.

I visited the first manufacturer, https://www.timbawood.co.uk, who said they had a problem onsite once with incorrect weighting and could not adjust, so while they would do it if asked they would not recommend it. I also looked at their display and saw a very large distance (far more than the recommended 3mm) around the parting bead and meeting real, so decided not to progress further with them. He said it was a display model, and probably there due to poorer quality - but after my previous problem in that area, I decided not to take the chance - see https://www.diynot.com/diy/threads/how-to-seal-sash-parting-bead.538544. On the link, they had other issues with windows, supplier refunded me in the end.

It was because of what timbawood said, that has made me want to research this product before committing to it. I was then really surprised that almost none of the UK suppliers use this approach, instead opting for ugly spirals or partial concealed spirals - I couldn't figure out why, as https://balancesystems.co looks almost perfect. So I wondered what was it I was not getting. But maybe UK markets just do it this way, as it's what they have "always done". You are right, balancesystems, said they are imported from Amesbury Truth. I was looking through the catalogue for the part, as maybe I could find a lot more out there under that name. However the only ones I could see where installed in the jamb and visible rather than the stile, but that might be my lack of knowledge meaning I'm not understanding the products.

I'm hoping to go to the second manufacturer this week who offer this product, http://www.savethesash.com. But very little details about their windows online. I'm a little obsessed now about a high quality builds, so very cautious of companies that I cannot find mention of, in any of the various forums out there.

I also went to the London show room for http://www.mumfordwood.com. Their stuffed looked really good, much better than i had installed. Although it was a normal spiral, but partially concealed. Mumford is mentioned a lot in various forums in positive tones, so if they probably offered https://balancesystems.co I would go with them. What was interesting, for me, is mumfordwood used a strip of velvet around the end of the parting bead, to the side of the vertical draught strip, where it meets the meeting rail. Seems to be going an extra mile for draught proofing, that I had not seen anywhere else. I have UFH in the room, under carpet, so I need to keep airflow change to a minimum.

The last one I want to speak to is https://westburyjoinery.com as John Mumford joined them, and again I saw positive discussions - but no idea what they are doing with regards to balances and concealment, and if it's different to mumfordwood.

The reason why i'm looking at this, is when we built the new room a reveal was not added to the brick. I was assured with spirals the buildup would not be much. However compared to all my other sash windows below it, that have reveals, it is considerable and looks ugly in comparison. I'm also shocked by how ugly the non concealed spiral was - our bathroom below has a partial concealed spiral. I suspect a poor installation, with additional cladding has exasperated this. So I'm now exploring two options 1) see if a new install and product can match my existing windows on lower floors. 2) add a reveal in the brick, for the new window to be recessed into. If 2 is necessary, I could revert back to pulleys and weights, but I'm tempted to add the reveal and still add https://balancesystems.co, as long as I can re-assure myself it's the right choice. As this is what the bathroom below has reveal + partially concealed spiral.

 

[JohnD]

I live an an area where a batch of houses were built using the Amesbury system. They are concealed, and not visible in use. You can set them for removal and lift the sashes out.

I am one of a few who has maintained them with replacement balances. Other homeowners have bought new (plastic) windows when the strings broke or the springs rusted. Due to coastal environment they probably last around 20 years. The ones I cleaned and sprayed with WD40 seem in fine condition. I also wash the velvet rubbing strips, so they slide more freely, very occasionally.

The people with new plastic windows have much thicker frames and styles, which spoil the look of the tall, narrow window openings. They are also plastic.

I originally bought replacements from a hardware retailer in Miami who had a workshop and assembled them, but they don't like overseas orders. I have an idea I might have paid around £20 a pair.

 

[Mmark]

I see the "pinnacle", but it says it's installed in the jamb. Rather than in the stile.
https://www.amesburytruth.com/products/residential/window/hung/balance-systems/

If it's in the jamb, it will be visible. I couldn't find their product that would go in a timber stile.

 

[JohnD]

Mine is not pinnacle, but probably the preceding design. It is clipped into the frame, then the sash is slid onto it, and it travels up and down with the sash. You can't see it when in service. There is a groove in the side of the sash, and the plastic end cap at the top of the unit wedges into a matching plastic receptacle in the side of the sash.

A video will help you visualise it.

Have a look on YouTube for " how to remove and refit" for cleaning or maintenance.

 

[Notch7]

What was interesting, for me, is mumfordwood used a strip of velvet around the end of the parting bead, to the side of the vertical draught strip, where it meets the meeting rail. Seems to be going an extra mile for draught proofing, that I had not seen anywhere else

All of the big timber joinery manufacturers will have had their windows tested for air leakage, so you won't find Mumford and better or worse than others.

The furry stuff has its own problems: the bit exposed externally gets dirty and goes all mouldy and dirty.

George Barnsdale have got over this by using aquamac 21 weatherseal in a sliding application....Ivecused this system to make box dashes it works well.



If you want traditional windows with no balance, why not go for proper boxes with weights? Long term they have less maintenance issues. Balances are a pain.

 

[Mmark]

George Barnsdale have got over this by using aquamac 21 weatherseal in a sliding application....Ivecused this system to make box dashes it works well.

I had a quick look at the George Barnsdale CAD diagrams, looks nice. Wish I could see some close up photos. I have some from Mumford Wood and TimbaWood, see below. I must admit I have preference for the hard foam or nylon. My understanding is on new windows they seal better, with better acoustic performance and certainly less visible on the eye. If anyone is able to add any for George Barnsdale or Westbury, that would be appreciated.

If you want traditional windows with no balance, why not go for proper boxes with weights? Long term they have less maintenance issues. Balances are a pain.

If i have to add a reveal, I may indeed go back to traditional. In part because i'm getting confused by what I read online about comparisons of advantages and disadvantages. The https://balancesystems.co looks nice, but without enough knowledge to make a decision here, may stick with traditional.

All of the big timber joinery manufacturers will have had their windows tested for air leakage, so you won't find Mumford and better or worse than others.

It's often hard to know what is a large reputable and what is not. Our builders picked a reputable local company, the build install was awful. The gaps around parting bead where nearly 1cm around the side and too with really bad draughts when windy. the window would rattle and bang as you moved it up and down. One of the spirals would "thwack" noise as it went up too. They had no weather seals on the parting bead, they came back to add those weather seals, but it clearly wasn't a correct install. They just stuck them on the window, but only to cover the meeting rail area, and not the full length of the parting bead, and then the piles started coming off. See image below, and that one had one of the smaller gaps. In the end they just refunded me. So I'm now looking to redo it all, properly.

 

[Notch7]

It's often hard to know what is a large reputable and what is not. Our builders picked a reputable local company, the build install was awful. The gaps around parting bead where nearly 1cm around the side and too with really bad draughts when windy. the window would rattle and bang as you moved it up and down. One of the spirals would "thwack" noise as it went up too. They had no weather seals on the parting bead, they came back to add those weather seals, but it clearly wasn't a correct install

Builders tend to use a local joiners they know, theres a "scratch my back" relationship.

The problem with small local joiners is that they don't specialise in windows and they haven't spent huge amounts of time and money on research and development to iron out all the complications that can occur in windows. With sliding box sash windows, there's the complications of weatherseal, parting bead, meeting rails, balancing. (I know, I used to own and run a local joinery shop employing half a dozen people).

Unfortunately it sounds like your windows had some design errors, with either the parting bead spacing or gap between sash and box frame incorrect. When using the furry stuff, I made box sashes with 3.5mm gap on the sides and 2.5mm gap between sash and outer facing and sash and parting bead.

It's not that hard...I never had issues with droughts, you just have to get the gap correct for the weatherseal to compress enough, but not too much so it makes the sash difficult to slide.


We planted on a taper piece for the meeting rail and used aquamac 21 as a compression seal.



I would say Mumford and Wood (part of performance window group) or Westbury are very good.
Mumford are pretty expensive, but the product is high end. Westbury are an orangery manufacturer- good company to deal with.

Timberwindows.com if you want to pay top dollar!

George Barnsdale are very well established, I'm sure their product will work well with no issues.

If you wanted to try a smaller company, there's GlynGary - they've been making box sashes for donkeys.

Or you could try Input joinery


There's Bereco, but I think the styling might be more modern and they may only supply through dealers

 

[mrrusty]

For our house I recently DIY made a whole house (8 windows) of sash windows in accoya pretty much following the CAD drawings Mumfords put on line. The clearances Notch posts above are what I worked to near enough, except I was down to 3mm and 2mm. I used a variety of seals all from reddiseals and it all worked really well. For my meeting rail I used a double brush, which also has proved really good in service.

I made them because after researching the market I found Accoya windows by good makers were outside my budget.

One thing I wish I'd done in hindsight, is design some of the upstairs windows (over a single storey extension) to use the scottish simplex system for easy cleaning.

 

[Mmark]

I looked over the George Barnsdale CAD diagrams and found a picture online. I can see the Aquamac 21 on the stile, but it looks like there is nothing on the parting bead, makes me wonder if the leaves a bigger opportunity for air exchange.

The TimbaWood instead places two nylon strips, one on the parting bead the other on the staff - so it's either side of the sash. And a third on the stile. Not the best photo, but you can see the two strips to either side.


I don't have he photo, but the diagram shows the one on the stile:


The Woodford and Westbury rely heavily on piles. From what I read the nylon/foam options of TimbaWood and George barnsdale should give a better seal. The three seal system of Timbawood, superficial, seems superior to the George Barnsdale one. So I'm tempted to go back to TimbaWood.