I have been a joiner & boat ﬁtter for 25 years and I have been making double glazed boat windows for 15 years. I have made them for Narrowboats and Wide Beam vessels as a replacement or for new builds. The need for a suitable replacement for “bus windows” is growing.
The main problem with them has always been condensation,which in time leads to linings rotting and steel rusting. Other problems are draughts, ventilation is one thing, unwanted draughts increase heating bills. Double glazing in a boat also provides sound insulation and better security. As all my windows are hand made they can be any shape or size from bow top, round, rounded corners or square.
The openers for Boat Windows are usually inward opening Hoppers except for side opening hatches on Narrowboats that can open out all the way onto the sides of the boat. With Hoppers the top section can open or the whole window, if large enough they can then be used as escape hatches. Openers are kept closed with a neat Fitch Fastener and held open an inch or two with a Roller Stay,which when lifted up out of the way allows the whole window to open fully. The ﬁttings I use are made by Carlisle Brass.
Timber Options: The Timbers I use are Mahogany – Utile and Sapele, English and American Oak, Douglas Fir and Teak.
– Mahogany is a good choice for this sort of joinery, easy to maintain, Utile and Sapele are similar in colour, Sapele has the stripy grain,good for architraves.
– Oak is durable and heavy, but it will go dark outside,needs more maintenance, but still worth considering, English Quarter Sawn Oak can be used for architraves, beautiful when polished. With the windows I make you can have low maintenance Utile outside with Quarter Sawn Oak or any other timber inside.
– Douglas Fir although classed as a softwood is a durable timber,often used for boat building Similar to Pitch Pine with its straight clear grain. -Teak, once difﬁcult to obtain is now widely available thanks to good forestry management, Teak of course is the most durable,and the most expensive, easily maintained with Teak Oil or similar.
Notes on Construction & Fitting:
What ever the shape of the window or the timber used the construction is the same and the only adhesive I use is West System Epoxy, commonly used in boat building applications.
– Openers are made with Mortice & Tenon joints, these are wedged.
– The curves on a Bow Top or round cornered window are laminated from two pieces,this makes for a very stable section.
– All the miters on the architraves have a biscuit joint to prevent any movement.
– The glazing is ﬁtted in the workshop using Sika-Flex, this provides a very strong and ﬂexible cushion.
– As for ﬁtting windows are bonded on with Sika-Flex, the paint behind the architraves having been cleaned and any rust removed and primed. The windows are then screwed to the ﬁtting out battens, not the steel like some other windows with stainless screws leading to rust. As with anysort of boat window they need to cope with the steel or ﬁber-glass ﬂexing, often exaggerated, Sika-Flex will cope with any movement.
Advantages of Hardwood Boat Windows:
– Warm frame = No Condensation.
– Double Glazing as Standard, 20mm minimum up to 30mm. The same insulation qualities for heat & sound as a modern house window.
– Glazing Options, always safety glass-laminated or toughened, but also obscure of your choice, Pilkington K to allow heat in or Solar control to keep the heat out.
– Choice of Timber: With a laminated frame why not have a less durable but more decorative timber on the inside such as Ash, Maple or Quarter Sawn English Oak to compliment your ﬁt-out.
– Architraves, all the windows I make are made to measure and they are supplied complete with internal architraves so no need for bits of beading. Architraves can be inlayed with Ebony & Rose Wood Banding’s.
– Best quality brass ﬁttings that are widely available should they ever need replacing.
– Draught prooﬁng – all openers are sealed with Aquamac seals.