Conservatories, Sunrooms - Your questions Answered
Hardwood and Timber (12)

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This question is answered by the Conservatories Online editorial team - Most suppliers will supply you with suggestions/instructions for decoration preparation when they deliver the conservatory. Generally speaking most companies advise you to first treat the timber with a preservative. Then if you are painting most will suggest using a micro-porous paint system - which allows the timber to breathe. One brand we recommend is Cuprinol. Ask at a specialist paint merchants about micro porous paint systems. We are grateful to Mike Jackson at Baltic Pine Conservatories for help in answering this question.

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Question submitted by Katey

How can I tell whether a conservatory company is high quality or not? It seems that some companies that offer hardwood conservatories are really only supplying the wooden equivalent of the system PVCu products rather than something that would truly look good on an Edwardian house.

This question answered by David Salisbury - There is only one way to be sure that a conservatory has the feel you want, it is also good general advice. You should ask to see a conservatory installed by the company you are interested in. The glossy brochure is not necessarily a good guide to the product. If possible arrange to see a conservatory installed in a domestic setting and talk to the customer about the service they received.

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Question submitted by Katey

Is the airspace between glass a clue to the quality of a hardwood conservatory - One leading supplier uses only 6mm air gap whilst others are 20mm which gives a much more "double glazed" and therefore modern feel.

This question answered by Tina Dunlop - Generally speaking air gaps of 12 mm - 16 mm are considered the best in terms of insulation when it comes to fitting double glazed units in hardwood conservatories. That said there are occasions when a smaller air gap may be preferred - especially if you are trying to create as "authentic" a feel / look as possible for say an Edwardian or Victorian design. After all in those times the only alternatives was single glazing. The thicker the sealed unit then the thicker the framing needs to be in order to accommodate them. This is especially so if you are trying to replicate a traditional look such as Georgian "margin" bars or Gothic arches. A criticism sometimes leveled at double-glazing is the "thickness" of framing required - this off course will not always be acceptable to the "pure" traditionalists. An alternative to having thicker margin bars / arches in this situation is to "plant on" thinner margin bars / Gothic arches on top of a double glazed unit. (This way the bars / arches can be quite slim as the double glazed unit does not have to fit into them) With this alternative you can have the benefits of both a traditional appearance and modern double-glazing. This is the preferred alternative in my opinion.

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Question submitted by Mark

What should we paint hardwood with for low maintenance? Is it ok to use a coloured garden stain such as 'Garden Shades' by Cuprinol?

This question answered by Tina Dunlop - Garden Shades would not be the best alternative. Most painted hardwood conservatories have three separate coats of paint applied. First a spirit-based primer followed by a water based topcoat (usually factory spray applied) - then a final brush coat is applied on site. All paint primers and finishes should be microporous allowing the timber to breathe naturally. I suggest you approach a specialist paints supplier and enquire on their recommendations for microporous paints to use on timber.

This Question answered by Tina Dunlop - Red Cedar (actually a type of softwood) is a perfectly fine material for conservatories. It is no better nor worse that a suitable hardwood and is also similar in cost. When selecting hardwoods it is generally considered best to use a "close grained" alternative such as IDIGBO. This hardwood machines well plus is very strong and durable. You may wish to ask your potential suppliers about the "closeness of the grain"! I would say West African hardwood from sustainable plantation sources is probably the most popular of the Hardwood alternatives.

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Question submitted by Richard

You quote several conservatory materials, but exclude pine. Do you see any problems with this material?

This Question answered by David Salisbury - Pine is a perfectly good material for external joinery of all kinds and has of course been used as such for many years. All Materials have their advantages and disadvantages in every application. I list some of the most important Advantages and Disadvantages for pine in relation to conservatories below ADVANTAGES 1. Cheap. 2. Easy to machine 3. Renewable resource. 4. As with other timbers but unlike UPVC has good structural strength without reinforcement 5. Along with other timbers can be fashioned to all kinds of shapes and mouldings to suit individual requirements and can be used to match traditional styles. DISADVANTAGES 1. It is very important that the timber is correctly treated with deeply penetrating preservative to prevent rot. Most other timbers commonly used are more expensive but do not require this treatment. 2. Knots have a tendency to bleed resin through paint finishes. 3. Of all timbers, Pine is most prone to movement (i.e. the seasonal swelling and shrinkage as the moisture content rises and falls) This can lead to doors and windows binding and causes stress to paint finishes. 4. It is relatively soft, being easily damaged.

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Question submitted by Michael

I am getting totally conflicting advice on the suitability of Western Red Cedar for my conservatory (as used by Amdega). Is this as good or better than a hard wood?

This Question answered by David Salisbury - Western Red Cedar is a perfectly fine material for conservatories. Neither better nor worse that a suitable hardwood and is also similar in cost.

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Question submitted by Debra

What is an Orangery exactly?

This Question answered by David Salisbury - Orangeries were a fashionable addition to stately homes and country houses in the last century. The classic design had stone built parapet walls containing large vertical sliding sash windows such that the glass area on the sides was in excess of 75%. They had a glass roof on timber rafters with a box gutter (usually cast Iron) all round inside the parapet wall. They were separate from the house and used for growing oranges, lemons and other exotic plants. Today the term "Orangery" has become fuzzier, referring to a largely glazed building with a glass roof. Often now attached to the main house and used as room as well as for plants."

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Question submitted by Raswan and Sheila

We are in the process of buying a hardwood conservatory. One of the companies we are considering does not use the comb joints system when constructing window frames and doorframes. Instead they use plain 45 degrees joints that are glued together and then a jig is used to force two metal chevrons into grooves pre-cut into the faces of the joints. They claim that this system is as strong as the comb joints with the advantage that none of the faces of the wood with the grain is exposed to the rain and therefore less likely to absorb water.

This Question answered by Tina Dunlop - I am familiar with this product. For assistance in answering this question I consulted David Salisbury of David Salisbury Conservatories (www.dscons.com). Whilst David could hardly claim to be impartial I think you may find his feedback of interest in any case. Here is his reply. "Mitred joints as you describe have been widely sold. Many joiners would argue that this is an inferior system because mitred joints inevitably open up when the wood expands and then water is allowed into the joint (note what happens on a mitred timber sill). While it is true that a mortice and tenon joint on a casement exposes end grain this will not be a problem if factory sealed. Argument could rage between partisan opinions on either side, but it is not true to say that the mitre is a clearly superior system, and most traditional joiners would disagree." Speaking personally - I do not care for the method you describe in your question. It has been primarily designed for speed and offers a similar manufacturing process to mass-produced PVCu windows. It does not for me have that feeling of "authenticity" and you will not have that "bespoke" feel because your supplier is more limited in the range of sections they can use. (It's all based around standard sections.) Unless it is considerably less expensive than a traditional mortice and tenon approach I would not favour it.

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Question submitted by Jac

I fancy a white American oak conservatory, but 2 people have advised against it claiming it cracks and moves. Others say it is good if jointed properly. What do you feel about it?

This Question answered by Tina Dunlop - Opinion does vary on this - however most people (myself included) do feel American Oak is a suitable material for conservatories. It has similar qualities to many hardwoods and provided it is well produced and jointed properly you should have no problems. One reason it is not so popular is that it is often difficult to get the OAK in large enough sizes for construction. Only major disadvantage is its cost - it's one of the most expensive materials you can use to manufacture a conservatory.

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Question Submitted by Jacqui

In your experience what is the average cost of a hardwood conservatory of approx 30 square metres without the basework included, what would it cost in red ceder? A recent magazine article gave average prices for the whole range of available types but the quotes we are getting seem almost double, are suppliers trying it on or is the average price about £40,000?

This Question answered by Tina Dunlop - Prices vary greatly - but it does not surprise me to see you have been quoted up to £40,000. As a guide most bespoke - top of the range hardwood conservatory companies charge £1,200 - £1,500 per square metre inclusive of ground works and fitting. As an example using the £1,200 per square metre rate that would mean a cost of £36,000 inclusive. To supply the conservatory only would cost about £25,000 - £28,000 depending on how bespoke it is. I consulted Oakleigh Conservatories and David Salisbury Conservatories for theses rates. There are links to both these companies in our "find a supplier" sections. Red Cedar would, I am told, cost similar to hardwood. I hope this helps.

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Question submitted by Joe

We have seen extensive material on Amdega conservatories and particularly like the detailing. Their literature is impressive. Before committing to an expensive project I would like some "almost impartial" information on the Amdega line. Is it really "the best"? Are they a healthy company that can be counted upon for the long term? Your input would be greatly appreciated.

This Question answered by Tina Dunlop - Amdega is one of the oldest and most widely known brands in the UK and there is no reason to suppose that they are anything other than financially sound - although there have been some upheavals in the management and ownership of the company in the last few years. A lot of it comes down to taste. If you like their particular detailing and style, then this must count for a lot. Their marketing and literature is certainly excellent. In the UK Amdega could now be best described as a mass-market company. There are several other UK companies that specialise in upmarket installations that you could look at for a comparison if your budget is not too tight. If you are in the US - Amdega do have representation there also. They have recently updated their web site at http://www.amdega.com Other US sites worth a visit are http://www.britishrose.com/ (British Conservatories) http://westviewproducts.com/ (Westview Products) and http://www.tanglewoodliving.com/