York Guild Hall

i very rare type of a double-aisled roof with posts to the floor. I Mid-fifteenth century. 93 ft. long by 43 ft. span. About 30 ft. high.

itsrli takes no strain, and fulfils no purpose; it merely projects into the air, uselessly.

Another variety of false hammer-beam, one which is not constructionally sound, is shown in Fig. 44, No. 21. This is known as the pendentive type. The roof at Eltham Calace is an example. Instead of the hammer-posts bearing on the hammer-beams, they are taken down beyond them, in decorative moulded finials, and the ends of the hammer-beams are tenoned into them. The support to the hammer-post, therefore, is not on the hammer-beam itself, but only on its tenon. It is obvious that this method is constructionally bad, as the Office of Works discovered when the Eltham Palac» roof was recently restored and reinforced.

\ compound roof is one where the span is too wide to be bridged by tie-beams at wall-plate levil. The hammer-beams, in a roof of this kind, carry vertical posts tenoned into principal rafters at their upper ends, and the tie-beams are fixed at about

LONG MELFORD, SUFFOLK.

LONG MELFORD, SUFFOLK.

purlin-level and are, therefore, in effect, collars ratherthan true tie-beams. Examples of compound or double-aisled roofs are illustrated here in Fig. 44, Nos. 21 and 24. Westminster Hall and Need h am Market Church, shown later in Figs, go and 83, are examples of these double-aisled roofs.

In view of the above explanation it is unnecessary to enter into a description of single-thrust or lean-to roofs. The principles are the same, and are self-evident.

No better understanding of the details of timber roof construction can be gamed than by the study of roofs of barns of the

STOKE-BY-NAYLAND, SUFFOLK.

The Xave. Late fifteenth century.

STOKE-BY-NAYLAND, SUFFOLK.

The Xave. Late fifteenth century.

L.ONG MELFORD, SUFFOLK.

The Xave. Late fifteenth century.

L.ONG MELFORD, SUFFOLK.

The Xave. Late fifteenth century.

more elaborate type, such as Harmonds-worth Barn, shown here in Fig. 45. Barn roofs are necessarily devoid of much of the decorative character usually found in those of churches or mansions, and there are, in consequence, no unnecessary details or parts to distract the attention. Barn roofs have also another advantage ; from their utilitarian, as distinct from decorative, character, they exhibit early details and constructional methods persisting to a later date. Being made for use only, their evolution is necessarily slow, as a perfect principle, once devised, was adhered to, irrespective of changing fashions, or desires for novelty in decorative effects. The supporting posts, which are the barn equivalents of the domestic hammerposts, have an advantage in reaching to the floor, whereas, in the great hall, they would be an obstruction. The barn roof, such as in Fig. 45, is, therefore, truly double-aisled at floor level, and it is this form of construction which must have inspired the hammer-post and hammer-beam. The stable properties of cantilevering the hammer-beam would follow when the carr\'ing of the posts to the floor was interdicted. Unfortunately, the supporting of hammer-posts on the tenons only of the hammer-beams (the pendenti\e type

Fig. 51. MONKS ELE1GH, SUFFOLK.

Roof of North Aisle. 10 ft. 9 ins. span.

Fig. 51. MONKS ELE1GH, SUFFOLK.

Roof of North Aisle. 10 ft. 9 ins. span.

Fig. 50. WETHERDEN, SUFFOLK.

Roof of South Aisle (c. 1400).

Fig. 50. WETHERDEN, SUFFOLK.

Roof of South Aisle (c. 1400).

such as at Eltham and Farl Stonham), must have originated from the same source.

York Guild Hall, shown here in Fig. 46, is a remarkable example of a roof supported by posts from the floor, forming, in effect, a hall with nave and aisles, and is, probably, the only roof of this kind existing in England at the present day. Although unique now, there is 110 doubt that this form is earlier than the hammer-beam roof ; in fact it must have been the prototype. York Guild Hall is late for this kind of roof construction. Begun in 1446, it was not completed until nearly fifty years later, and records exist which state that the merchants of York who were convicted of illegal practices were fined, not in money, but in kind, having to find timber and oak wainscot for the Hall.

The roof is low in pitch, with little outward thrust, the great stresses being almost entirely downwards, carried on the massive octagonal-section oak posts with their stone bases. The nave is of the firred-beam type. The aisles are constructed with simple lean-to roofs. The problem of the entire roof, therefore, is one more of size than constructional

Hislu Roof. 48 ft. long by 9 ft. span. Fifteenth century. The western type of panelled roof.

Hislu Roof. 48 ft. long by 9 ft. span. Fifteenth century. The western type of panelled roof.

Fig. 52. ROUGHAM, SUFFOLK.

Roof of South Aisle. Late fifteenth century.

Fig. 52. ROUGHAM, SUFFOLK.

Roof of South Aisle. Late fifteenth century.

difficulties, involving complicated stress calculations. The principles governing roofs, even of gigantic size, where the timbers are supported from wall-head level, were fully understood, and their advantages appreciated at this date. There are many factors, other than inexperience or timidity on the part of the medieval carpenter, which may have dictated this aisle-column form of the York Guild Hall roof.

A careful study, and memorising of the roof sections illustrated in Figs. 43 and 44 is recommended, as in the illustrations which follow, of actual roofs, the essential details cannot be shown so clearly, as in diagram form. Apart from lighting considerations, with concomitant photographic difficulties, the occultation of the one beam or collar, with its superimposed bracing or posts, by the succeeding one, renders the close stud}' of all the points of a roof, from the one view point only, nearly impossible. With a single photograph, therefore, all the details of a roof cannot always be shown distinctly. Space considerations preclude a redundancy of illustration.

The succeeding illustrations have, -for convenience only, been arranged in a progressive order, from the simple to the complex. \\ lnle there is no doubt that the true evolution of the timber roof actuallv took place somewhat on these lines, it must not be assumed that a simple roof is earlier in date than a more elaborate one. We have no complete record of very early roofs ; the greater number have perished, disappeared and been forgotten long since. At one period in the history of English carpentry, examples could have been illustrated to show the development from type to type, each true to the date of its inception, but that time has passed, many centuries ago. Thus the gigantic roof of Westminster Hall, dating from the closing years of the fourteenth century, is an early example when compared with others existing at the present day, but it is late in the history of the English

Roof of North Aisle.

Roof of North Aisle.

timber roof. An enormous span of 68 feet between walls would have been impossible to bridge at the dawn of timber-roof construction. It is conjectured that the original roof, which the present one replaced in 1395, was constructed with two aisles and with posts to the floor in the same manner as in Harmondsworth Barn or York Guild Hall, ahead}7 illustrated.

With the above stipulation, therefore, we can commence with the low-pitched roof of the tie-beam or firred-beam description, and illustrate, in an orderly progression, examples from this simple type to that of the ornate hammer-beam and double-aisled construction. No distinction has been attempted, nor is it possible .to make any, between the ecclesiastical and the secular types. Even if the difference between a secular and a sacred building had resulted in a change in constructional design due to such character, which was not the fact, —there are many examples in which both the sacred and the secular elements enter very largely. That many, if not all, of the earlier roofs were inspired from clerical sources, is probable, but this does not concern us here at present.

Fig. 47 is the roof of the Lady Chapel at Long Melford 'in Suffolk. This is of the cambered-beam type, and possesses, in addition, a rare diagonal beam from wh'ich two sets Of joists run at right

Fig. 55. LAVENHAM. SUFFOLK.

Fig. 55. LAVENHAM. SUFFOLK.

Fig. 56. KELSALE, SUFFOLK.

Span 21 ft. G ins. Earl}- fifteenth century

Fig. 57. MONKS ELEIGH, SUFFOLK.

Roof of Nave. Span 19 ft. 9 ins. Early fifteenth century.

Fig. 57. MONKS ELEIGH, SUFFOLK.

Roof of Nave. Span 19 ft. 9 ins. Early fifteenth century.

angles to each other. This is, in effect, another form of the dragon-beam referred to on page 42, although the term is not used in referring to the timbering of a roof, but only to the joisting of a floor. The principle, of supporting two sets of joists or rafters at right angles to each other, is the same in each case, however. The tie-beams to this roof are arch-braced to wall-posts, supported on the capitals of the slender wall columns.

Fig. 48 is the nave roof from the same church, also of cambered-beam construction. The ridge and

Historic Cambered Tie Beam

Fig. 59. LAPFORD, DEVONSHIRE.

Roof of the Nave.

Fig. 59. LAPFORD, DEVONSHIRE.

Roof of the Nave.

HORWOOD, N. DEVON.

The Roof of the N. Aisle.

HORWOOD, N. DEVON.

The Roof of the N. Aisle.

purlins are framed between the beams, the common rafters being tenoned into and pegged to the ridge. Both principal and common rafters are elaborately moulded. The clerestory windows are high, and tran-somed, and the columns of the aisles are delicate in proportion for the height of the nave, but with these low-pitched roofs there is practically no outward thrust, and the little there is, the wall-posts, to which the tie-beams are arch-braced, take up very efficiently. These wall-posts and the slender columns below them, rest, alternately, on the junctions and the apex of each arch of the aisles.

Fig. 49 is the nave roof of Stoke-by-

TAWSTOCK, N. DEVON.

The Roof of the Chapel. 40 ft. long by 15 ft. 9 ins. wide.

Fig. 61. HITCHAM, SUFFOLK.

The Roof of the Chancel.

TAWSTOCK, N. DEVON.

The Roof of the Chapel. 40 ft. long by 15 ft. 9 ins. wide.

pitch with a slight lean-to. The cambered - beams are enriched with carving of square rosettes and bosses, with heraldic shields covering the intersections of the tie-beams with the purlins. Only the alternate beams are arch-braced to the wall-posts; those between are merely tenoned into the carved wall-plate. The winged angels applied at the foot of each of the wall-posts are finely executed.

Fig. 51 is another lean-to roof from the aisle of Monks Eleigh Church. Here the beams are square sectioned, without camber, and rest on the wall-plates, which, in turn, are supported on plain stone corbels, and the last two main beams are braced to the wall-posts, the spandrels filled with early fifteenth-century pierced and carved tracery.

Xayland Church, in Suffolk, another eambered-beam roof, but here arch-braced to will-posts resting on stone corbels instead of the capitals of columns. The low rafter-pitch of this roof, and also the jointing of the arch-braces, can be clearly seen in the illustration. The roof has been considerably restored, and some of the tie-beams replaced, with the original mouldings omitted.

  1. 50 is the aisle roof of Wetherden Church, a lov-
  2. 61. HITCHAM, SUFFOLK.

The Roof of the Chancel.

Crosby Hall

CROSBY HALL.

Erected 1470, and n-ereeted in Chelsea, London, S.W., 190s.

CROSBY HALL.

Erected 1470, and n-ereeted in Chelsea, London, S.W., 190s.

Walter II. Godfrey, Architect.

  1. 52 ib the S. aisle, roof of Rougham Church, with each beam arch-braced on the S. wall, but, on the nave side with braces only to each alternate beam, carried down to posts and corbels at the junction of each arch of the aisle.
  2. 53, the aisle of Tawstock, N. Devon, shows the fifteenth-century western type of panelled roof.
  3. 54 is the roof of the N. aisle of St. Osytb Church in Essex. Here, both the beams and rafters are moulded, and the former elaborately carved. Each alternate beam is arch-braced to the wall-posts, these only having heavy carved pendentives at the intersections.
  4. 55 is the N. aisle roof of Lavenham Church, in Suffolk, a richer example, with alternate beams, only, arch-braced to the wall-posts. The foot of each wall-post is carved with the figure of a Saint, standing on the stone corbel. The
Scissors Bracing

The dotted lines show the finish of the original scissors-bracing. The parts shaded show the additions made by Mr. Walter H. Godfrey when the hall was re-erected. Erected in 1470 for Sir John Crcsby, d. 1475.

Section through the Roof.

CROSBY HALL.

famous pew of the Spring family, seen in the distance at the side of the chapel screen, will be illustrated to a larger scale in a later chapter.

The dotted lines show the finish of the original scissors-bracing. The parts shaded show the additions made by Mr. Walter H. Godfrey when the hall was re-erected. Erected in 1470 for Sir John Crcsby, d. 1475.

Section through the Roof.

CROSBY HALL.

Figs. 56 and 57 are the braced-rafter types, in each case, scissor-braced above the collar. In Fig. 56 each sixth rafter is arch-braced to corbelled wall-posts, the rafter being framed to the post with a sole-piece notched to the twin wall-plate, and the intermediate rafters arc strutted with ashlar-pieces from the wall-plate. In Fig. 57 there are neither arch-braces nor wall-posts. This is an early type of high-pitched roof, and shows the development towards the next form, the barrel, which is really an arch-braced instead of a straight-braced rafter roof. Examples are shown in Fig. 58, Horwood ; Fig. 59, Lapford ; and Fig. 60, Tawstock Chapel. Fig 59 is ceiled in to barrel-form above the rood-screen. Fig. 61 is a rare double-coved and barrel roof, close-boarded in. The side-covings really mask hammer-beams, which carry the longitudinal hammer-plate. This arch-braced rafter, or barrelform of roof is typical of Devonshire and Somerset Churches, although it is unsafe, at the present day, to attempt a classification of timber roofs into types of localities, without many drastic exceptions.

The roof of Crosby Hall, Figs. 62, 63 and 64, enters into the logical sequence of timber-roof development here, and also serves to show how narrow is the division line between a roof and a ceiling. Practically all of the visible woodwork of this roof is purely decorative, but the sectional view,—for the drawing of which wTe are indebted to Mr. Walter H. Godfrey, the architect under whose supervision Crosbj7 Hall was removed from its former site in Bishopsgate to its present location in Sir Thomas More's old garden at Chelsea,—shows that it is really of the scissor-braced rafter variety. In the drawing, the dotted lines at AA show the original bracing, which was in a veiy decaj'ed state at the time of the removal, and BB the new scissor-brace u hich was inserted by

Mm Godfrey, to strengthen the original bracing. At the same time the king-post C was also introduced. Fig. 64 is from an idealised sketch made by Herbert Cescinskv of the Hall before its demolition in 1908, and Fig. 62 shows it in its state as re-erected.

It is only this original scissor-bracing which removes this roof from the category of ceilings. Actually, a ceiling may be defined as the covering of a room or hall which is fixed to, and supported by either roof timbers or the joists of the floor above. Thus, the visible joists, even when carved and decorated, with the interstices filed in by the floor-boarding above, do not constitute a true ceiling, no part of which should be constructional, but merely decorative. Crosby Hall, therefore, can be described as having a ceiled decorative roof, of which the arched-ribs with their wall-posts are the only visible constructional members.

  1. 65, the nave roof of Haughley Church, in Suffolk, introduces the tie-beam roof. This is distinguished from the cambered or firred-beam types in being higher in pitch, and in consequence, possessing a ridge-purlin, but without collars. In this example, the tie-beam is introduced between each alternate principal only, and is braced below to corbelled wall-posts, and above, from the beam to the purlin. The intermediate principals are arch-braced to wall-posts direct. At the junction of each brace with its purlin, and each principal with the ridge, is an applied pendentive ornament in the form of a carved floral boss.
  2. GO is a secular roof from a house in Lad\' Street, Lavenham, in process of restoration. The tie-beams are cambered, and the rafters are halved at their intersections without a ridge-purlin. To compensate for this a collar-purlin is fixed under the collars, and this is stiffened by a braced king-post from the centre of the cambered tie-beam. The end of the tie-beam, visible in the illustration, illustrates the decay often met with in these early timber roofs, to remedy which it is necessary to take

CROSBY HALL, B1SHOPSGATE.

From an idealised sketch by 1 lerbert Cescinsky made in 190S.

CROSBY HALL, B1SHOPSGATE.

From an idealised sketch by 1 lerbert Cescinsky made in 190S.

HAUGHLE\, SUFFOLK.

The Roof of the Xave. Span 24 ft. 6 ins. Length 58 ft. 4 ins.

Late fifteenth century.

HAUGHLE\, SUFFOLK.

The Roof of the Xave. Span 24 ft. 6 ins. Length 58 ft. 4 ins.

Late fifteenth century.

the roof apart to repair it. In the illustration, it will be noticed that each joint has been marked to facilitate the re-erection.

Of similar type is the nave roof of Edwardstone Church in Suffolk, Fig. 67, where the sag of the tie-beams, in spite of their camber, may be noticed. All four braces from the king-posts are tenoned into the collars, instead of the lateral braces being carried past them to the purlins, as in the previous example. In addition to this support, the collars are braced to the rafters, which, in turn, are ashlar-strutted from the wall-plates.

Fig. 6S is the nave roof of St. John's Church, Henley-in-Arden, of the arch-braced queen-post type. The tie-beams have an acute camber, and are arch-braced to corbelled wall-posts. The collars are high and small in scantling, and the roof is without ridge-purlins. So rare is it to find the queen-post type of roof before the Dissolution of Monasteries, that the presence of these posts may be taken as an almost infallible indication of the latter half of the sixteenth century, or even later. St. John's Church has a fine pulpit, which will be illustrated in a later chapter on the development of the English oak chest.

Guild Hall Roof Truss
Fig. 66.

HALL OF TIMBER HOUSE IN LADY STREET, LAVENHAM.

King-post type of roof with collar-purlin. Middle fifteenth century.

Guild Hall Roof Truss

EDWARDSTONE, SUFFOLK.

Roof of Nave. Braced king-post and collar-purlin type. 17 ft. 10 ins. span.

ST. JOHN'S, HENLEY-IN-AKDEN, WARWICKSHIRE.

The Nave Roof. Braced queen-post type.

HOUSE IN THE BUTTERMARKET, IPSWICH

Known as " Sparrowe's House." Mew showing the roof timbers. Late fifteenth century. Span iS ft. 6 ins: Length 30 ft. o ins.

  1. 69 has a moulded collar-beam, with large arch-braces fixed to the tenons of the hammer-beams, in the pendentive manner. The pendentive ornaments have been cut away to make room for the later flooring. As pointed out earlier in this chapter, this pendentive hammer-beam form of roof is not sound construction, as the strain is carried on the tenon only, instead of the hammer-beam itself.
  2. 70 shows the chancel roof of Ufford Church, in Suffolk, which introduces the pendentive hammer-post type. This is a framed collar-truss roof. The crenellated collars have a very slight camber, and are braced above to the principal rafters, and below to the pendant posts. From these latter, arch-braces are taken to the wall-posts slot-tenoned into the principals below purlin-level. From the pendentive posts, shields are fixed at a parallel slope to the pitch of the roof, with curious devices painted upon them, illustrating symbols of the Crucifixion and the Passion. On the right-hand side, in the illustration, the first shield has the scourges, the second the pincers for withdrawing the nails from the hands and feet, the third the dice-horn which was used for the casting of the lots, the fourth the Crown of Thorns, and on the fifth the dice are represented. On the other side the first shows the spear with which the soldier pierced the Saviour's side, together with the sponge on a pole and the ladder used to ascend the Cross, the second the Crucifixion hammer, the third the thirty pieces of silver (in three piles), the fourth a Crusader's sword crossing with a Saracen's scimitar, and the fifth shows the dice again. Winged angels centre each of the great carved cornice.
  3. 71 is the nave roof of St. Osyth Church, of which that of the X. aisle has already been shown in Fig. 54. This roof is constructed of timbers of light scantling,

HOUSE IN THE BUTTERMARKET, IPSWICH

Known as " Sparrowe's House." Mew showing the roof timbers. Late fifteenth century. Span iS ft. 6 ins: Length 30 ft. o ins.

with a ridge and three purlins. Of these three the central one has a collar-beam arch-braced to hammer-beams, which in turn are braced to wall-posts without corbels. The roof is simple, without carving, and moulded only on the wall-plate, the under sides of the hammer-beams, and the purlins. The common rafters are ashlar-strutted from the top of the wall-plate. This may be described as one of the earliest types of hammer-beam roof, though of late date.

Fig. 72 is a richly decorated roof from Southwold Chancel. It is of the single hammer-beam and braced-collar type, boarded in below the collar and across the common rafters, thus forming panels between the collars, the principals and the purlins. The collar-panelling is omitted, and the boarding taken to the ridge, in the bay at the western end, this being directly over the rood-screen. The entire Chancel roof is richly painted, that of the Nave having the open timbering without decoration. This example is an instance of the dual ownership of the church, dating from very early times, the nave being the property of, and maintained by, the parishioners, the chancel belonging to

Fig 70.

UFFORD, SUFFOLK, CHANCEL ROOF.

Framed collar-truss with pendentives, braced to wall-posts. L ite fifteenth century.

Fig 70.

UFFORD, SUFFOLK, CHANCEL ROOF.

Framed collar-truss with pendentives, braced to wall-posts. L ite fifteenth century.

the church. The latter, therefore, is nearly always more elaborate than the former. The chancel was generally enriched to its decorative limit before any bMutifying of the nave was commenced.

The nave roof of St. Peter Mancroft, Norwich, Fig. 73, is one of a rare type, which may be described as a vaulted hammer-beam. A purlin,—which becomes, in effect, a cornice, - is tenoned to the free ends of the hammer-beams, the latter being masked by a groined vaulting, carried down to slender columns, with caps and bases, placed between the clerestory windows and supported on carved corbels. The roof above the vaulting is simple, with ridge and two purlins, without collars, arch-braced from ridge to cornice, with winged angels applied, over the cornice, at the feet of the arch-braces.

Framlingham has a similar roof, Fig. 74, to St. Peterf Man croft, but differs in being of the arch-braced collar type. The collars are fixed at purlin level. That the vaulting supports the cornice and hammer-beams, to any extent, is doubtful. It is mainly, if not Entirely, a decorative detail.

Fig. 75 has cambered collars arch-braced to hammer-beams. The base t|p.ch of

ST. OSYTH, ESSEX, NAVE ROOF.

Collar-beams braced to hammer-beams. Late fifteenth century.

ST. OSYTH, ESSEX, NAVE ROOF.

Collar-beams braced to hammer-beams. Late fifteenth century.

Braced Oak Camber Beam
Fig. 72.

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