Have you ever looked at the chimneys in St Leonard’s?

Have you ever looked at …

… the chimneys in St Leonard’s?

Unless you are a builder, or have needed repairs to a chimney, you probably haven’t given much thought to the features of chimneys. How about a walk to look at some of the variety of chimneys in our neighbourhood?

What is a chimney anyway? According to the dictionary, “A chimney is a structure for venting hot flue gases or smoke from a boiler, stove, furnace or fireplace to the outside atmosphere.” In many modern houses, there are no chimneys, and the “hot flue gases” are vented through the walls. But chimneys were essential parts of most houses until quite recently.

A good place to start looking is at the end of Magdalen Road. Look across the valley to the Hotel Barcelona, the former Eye Infirmary, built early in the 20th century. It has splendid brick chimneys, with decorations and embellishments. You can see them in detail from close to, but these are chimneys that are designed to be a feature seen from afar. Even from here, you can see the chimney pots, the capping around the pots, and the brickwork which is there to strengthen and decorate the chimney stacks. Each pot corresponds to one fireplace in the building, and the layout of the rooms was – to some extent – dictated by the location of chimneys, fireplaces and boilers. Chimneys work best if they are vertical, or not far from vertical. However, the architect of any building with chimneys has to reach a compromise between the needs of the inhabitants for warmth, cooking and hot water, and the construction demands of chimneys. Until comparatively recently, fireplaces were an important source of heat, but each one needs a well-designed chimney.

Chimneys are expensive to build, for many reasons, because they are subject to variations in temperature and they need to be properly insulated from the rest of the building. (Look at a thatched house in the country; nearly always, the chimney is at the end of the house, so that the hot gases are in minimal contact with the thatch.) There are very specific building regulations concerned with chimneys. They need to extend above the roof, and in most houses, they extend from on or near the roof line to be the tallest part of the building. That ensures the dispersal of the waste gases, but means that the chimney stack has to be strong. It also means that they need to be well protected where they meet the roof, to prevent rain and snow penetrating through the join. Building houses with Lego doesn’t inform you about the technicalities of their chimneys, does it!

The almshouses in Magdalen Road have a magnificent set of chimney stacks, topped with matching chimney pots. The architect of these was clearly trying to make a lasting statement! With this height, they probably give a good draught to the fireplaces below; I wonder whether some of the residents found the draught too great as it would lead to increased consumption of wood and coal.

Walk up Magdalen Road, and into the older streets, and you will see a wide range of shapes and designs for chimneys. Over and over again, the builders and architects have been determined to mark the highest point of buildings with an attractive feature. There is a great deal of fancy brickwork to be seen, with chimney stacks that are rectangular, hexagonal and octagonal. Varied colours of bricks can be seen, and stacks are stepped outwards to give strength to the structure and protection to the pointing and roof below.

Then there are the chimney pots and the caps that protect them (more or less) from the elements. Pots are cheap ways to make the flues a little higher. Looking at them, you will see that pots are disposable; over the years, the pots in what were once matched sets have gradually been replaced, and the new ones don’t match. So there is a tremendous variety. Spot the pots with crown-like tops, those with one ring around them, or two rings, or three rings, and those with two colours of clay. Denmark Road boasts one pot with a star design; if you walk just beyond our area, the presbytery in Heavitree has several fine pots.

If you go to County Hall grounds, it is interesting that Belair does not have any chimneys.

The caps vary as well, from metal cowls to domes and clay lids. Once you start looking, you’re sure to find that there is plenty of provision for hot air in St Leonard’s and not just in election times. (May 2010 saw a General Election in the U.K.)

A chimney on the almshouses in Denmark Road:

The chimney below was not mentioned in the article; it is at Trews Wear.