(see Screen), which divides the chancel or the choir from the nave. The rood was carried either on a transverse beam, the “rood beam,” or by a gallery, the “ rood loft.” Such a gallery was also used as a place from which to read portions of the service (see Jubé). It was reached by the “rood stair,” a. small winding stair or “ vice.” In English churches these stairs generally run up in a small turret in the wall at the west end of the chancel; often this also leads out on to the roof. On the continent of Europe they often lead out of the interior of the church and are enclosed with tracery, as at Rouen or Strassburg. “ Rood stairs ” remain in many English churches where the rood loft has been destroyed. A fine example of a rood loft is at Charlton-on-Otmoor, Oxfordshire. The screen might be separate from the rood beam or rood loft. The general construction of wooden screens is close panelling beneath, on which stands screen-work composed of slender turned balusters or regular wooden mullions, supporting tracery more or less rich with cornices, cresting's, &c., and often painted in brilliant colours and gilded. The central tower of a church over the intersection of the nave and chancel with the transepts is sometimes called the “rood tower”; an example is that at Notre Dame at Paris. In England rood lofts do not appear to have been introduced before the 14th century, and were not common till the 15th. The “roods ” themselves were not disturbed in Henry VIII.’s reign, but were generally removed under Edward VI. and Elizabeth.
The legality of rood screens or rood lofts in the Church of England depends on the law of the Church with regard to images, i.e. “whether they do or do not, or will or will not, encourage or lead to idolatrous or superstitious worship in the place where they are, or are to be put” (Lindley, L. 7. in R. v. Bishop of London, 1889, 24 Q.B.D. 213, 237; see also St John Timberhill, Norwich, case, 1889 Prob. 71, and article Image).
ROOFS. A roof is a construction placed as a covering over
the upper portion of a building to exclude the weather and
preserve the contents dry and uninjured. Roofs are designed
to throw off rain and snow, and their slope or “pitch,” as it is
generally termed, is governed to a great extent by the climate,
as well as by the material used and manner of laying. The
pitch may vary from an almost horizontal surface (as largely
adopted in dry countries and also in temperate climates for
roofs of metal or asphalt) to the steeply pitched roofs required
for the ordinary flat tiles which to be weatherproof must be laid
at an angle of from 45° to 80° with the horizon. Besides serving
the useful purpose of protection against inclement weather the
roof, both externally and internally, may be designed to form
an architectural feature in keeping with the character of he
building.
The simplest form is the “flat roof” consisting of horizontal wood joists laid from wall to wall as in floor construction. The roof must not be quite flat, for a slight fall is necessary in its upper surface to allow water to drain away into gutters placed at convenient points. The joists are covered with a waterproof material such as asphalt, Forms of roof. lead, zinc or copper, the three last materials being usually laid upon boarding, which stiffens the structure and formsagood surface to fix the weatherproof covering upon. Such roofs are not suitable for cold climates, for accumulations of snow might overburden the structure and would also cause the wet to penetrate through any small crevices and under flashing's. With flat roofs the pressure exerted upon the supports is directly vertical.
“Lean-to,” “shed,” or “pent” roofs are practically developments of the flat roof, one end of the joists (which are now called “ rafters ”) being tipped up to form a decided slope, which enables slates, tiles, corrugated iron and other materials to be employed which cannot be used upon a “flat” roof.
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| Half elevation; 25′ 0″ span. | Sectional elevation on AA. |
| Figs. 1 and 2.—King-post Roof Truss. | |
Simple roofs in general use with a double slope are the “ coupled rafter roofs, ” the rafters meeting at the highest point upon a horizontal ridge-piece which stiffens the framework and gives a level ridge-line. In some old roofs the rafters are connected without any intervening ridge-plate, with the result that after a time the ridge instead of remaining level takes on a wavy outline, due to the fact that some of the timbers have settled slightly owing to decay or other causes, whilst others have remained firm in their places. The lower ends of the rafters should pitch on a wood plate bedded on the top of the wall; this, as described under Carpentry, assists in spreading the weight over a large area of the wall, and provides good fixing for the timbers. The simple “ couple roof” consists merely of two sets of rafters pitched from plates on the walls on either side of the building and sloping upwards to rest against a common ridge-piece. There are no ties between the feet of the rafters, which therefore exert a considerable thrust against the supporting walls. On account of this and of the lack of rigidity of the framing this form of roof should only be used to cover small spans of ro to 12 ft. Generally the ends of the rafters are connected by ceiling joists which form a level ceiling and at the same time prevent any outward thrust on the supports. When used for spans between 12 ft. and 18 ft. a binder supported by 'an iron or wood “king” tiepevery 5 or 6 ft. should be run along across the centres of the ceiling joists and the latter spiked to it. Such roofs with the wood tie across the feet of the rafters are termed “ couple close roofs.” When the ties are fixed about half-way up the rafters it is called a “ collar roof, ” and may be used for spans up to 16 ft. These are the type of roof commonly used in ordinary dwelling-houses where the
