This section is from the book "Spons' Mechanics' Own Book: A Manual For Handicraftsmen And Amateurs", by Edward Spon. Also available from Amazon: Spons' Mechanics' Own Book.
Thatchers' tools are as follows : - A common stable fork is used to toss the straw up together when it is wetted, preparatory to its being made into bundles for use. A thatchers' fork, Fig 1345, is a branch of some tough kind of wood, cut with 2 smaller branches proceeding from it, so as to form a fork, as shown; the joint of the 2 branches is generally strengthened by a small cord, to keep it from splitting when it is used. A small cord is fastened by one end into one of the ends of the fork, and a loop is spliced on the other end of the cord; this loop is made to pass over the other end of the fork, and to fit into a notch cut to receive it. This tool is used to carry the straw from the heap, where it has been wetted and prepared, up to the thatcher on the roof, where it is to be used.
The thatchers' rake, Figs. 1346 to 1348, should have a handle of ash or some tough wood, made square, so that it may be grasped firmly without fear of its slipping round in the hand : the arrises may be slightly rounded off, so as not to hurt the hand. It will be seen by referring to Fig. 1347 that a crook is formed in the handle; the reason for this will be explained when we come to speak of the manner of using the different tools. The use of this tool is, after the straw is laid, to comb it down straight and smooth.
The thatchers' knife, or eaves' knife, is similar in shape and make to the reap-hook, except that it is larger, and not curved so quickly. The use of this tool is to cut and trim the straw to a straight line at the eaves of the roof.
The thatcher also requires a knife shaped something like a bill-hook, to point the twigs used for securing the straw; a half-glove or mitten, of stout leather, to protect the hands when driving in the smaller twigs, called spars; a long flat needle, Fig. 1349; a pair of leather gaiters, to come up above the knees, to protect his knees and shins when kneeling on the rafters; a sharp grit-stone to sharpen the knives.
As before stated, the rafters for a thatched roof may be of round timber, such as the branches of trees, and young trees, of 3-6 in. diam., placed not more than 14 in. from centre to centre, but sometimes the rafters are of sawn timber: in that case they should be cut about the same scantling as for a slated roof, not as for a tiled roof. The lathing in a thatched roof being very liable to rot, it should be split out of heart of oak, or some other equally durable wood; the laths are about 1 1/4 in. wide, and 1/4-1/3 in. thick, and are nailed on the rafters about 8 in. apart in a horizontal direction, just the same as for a tiled or slated roof. If the laths are placed farther apart than 8 in., the straw is apt to bag or sink down between them; the rain lodges in the hollows, and of course soon rots the straw. An eaves' board about 7 in. wide is required to start the first part of each course of thatching upon.
The rafter and eaves' board being fixed, and the lathing nailed on in rows at the prescribed distance apart before mentioned, as much straw is taken as it is thought will be required for the whole roof, which may be got at by estimating a square to take 31/4-33/4 cwt. of wheaten straw : care should be taken to keep the fibres or stalks as parallel to each other as possible. As each truss of straw is opened, it is spread out and wetted, using about 3-4 gal. of water to each truss. The straw is then tossed over and mixed together in one great heap with the stable fork, so that every part may get an equal portion of the water. If the weather is fine and dry, the straw may be used directly; but if the weather is damp or rainy, the straw should be allowed to lie for a day or so to drain, and be once more turned over. The reason for wetting the straw is to make it lie close, and to enable the thatcher's labourer more easily to draw the stalks out parallel.
The thatcher and his labourer being now ready to commence, the labourer spreads as much of the straw on the floor as will make a bundle 12 in. wide and 4 in. thick; the labourer then stooping down, with his left hand draws the straw, little by little, to his feet, and while doing so, with his right hand draws out any loose straws that may be lying crosswise: by this means he gets a compact bundle of straw 3 ft.-4 ft. long according to the goodness of the straw, and all the stalks are parallel. This bundle is called a "hellam." The labourer having placed 4-6 hellams crosswise in his thatching fork, he carries it on his shoulder up to the thatcher on the roof, in the same manner as a bricklayer's labourer carries a hod of mortar : the fork is secured on the roof by a small peg and a piece of string.
The thatching is now laid in courses 3 ft. wide, beginning at the right end of the roof, so that the thatcher works from right to left. The courses are laid parallel with the rafters, and not parallel with the lathing (as is the case in slating and tiling). Care must be taken at starting the eaves to have a good firm body of thatch, letting the straw hang over, to be afterwards trimmed with the eaves' knife to a straight and good-looking edge. A row of 3 hellams is placed on each succeeding lath in the course, and each row of hellams is secured to the rafters with a young tough twig, called a "ledger," about 4 ft. long and 1 in. diam.: each row of hellams is also secured to the row underneath it with 3 split twigs, called spars, about 2 ft. long, and 8 can be split out of a brunch 2 in. in diameter; they are pointed at both ends, and are then doubled in two, and the thatcher gives them 2 twists round in his hand, in the same manner as a rope is twisted : this gives the spar a splintery surface, and enables it to hold on when driven into the straw.
The thatcher has a leather glove on his right hand: and keeping his hand flat or open, he gives the spar 2 or 3 smart blows, sufficient to drive it into the straw; the leather serves as a protection to the hand. The spars must be soaked in water for some hours before they are used, in order that they shall not break in the doubling up.
The "ledger" is a tough twig, about 4 ft. long and 1 in. thick, as before described; one end is pointed, and driven or rather pushed 6 in. under the outside rafter of the course: it is then brought over the top of 2 rafters, and over the top of the hellams, and then secured to the inside rafter of the course with about 8 ft. of rope-yarn, by means of the long flat needle, thus holding down the row of hellams, and preventing them from slipping off the roof. In speaking of the outside and inside rafter of a course, it is meant by the outside rafter, the rafter that is farthest from the thatcher; and by the inside rafter the one that is nearest to him; and thus the inside rafter of one course becomes the outside rafter of the nest course.
The thatcher gives each course, as it is laid, a combing down with his rake, to get out the loose straws : he then takes a bucket of water, and throws it right down the course, and gives the straw a good beating with the back of his rake, to break any stubborn straws and to make it all lie close: he then finally gives it another combing, and after that smooths it down with the back or flat side of his rake, and it is finished.
It will be seen by referring to Figs. 2078 and 2080, that a crook is formed in the handle of the rake. The reason for thus crooking the handle is to keep the thatcher's hand from contact with the straw, and thereby save his knuckles.
The ridge and hips are managed thus : - The thatcher, in doing one side of his roof, takes care to leave a good length of screw hanging over and past the ridge. As he finishes the top of each course on the other side of the roof, he bends down the tops of the first side, and covers them over with the last row of hellams on the last side, bending these last in their turn down over the other side of the roof. The ridge is then secured on each side with 3 rows of bands or spars, placed end to end, and each spar is secured with 3 other spars to thatch. In the case of the hips, there are no bands of spars, but single spars, 12 in. apart, are bent crosswise over the hip, and secured with 3 other spars, as before. The eaves are also secured with 2 rows or bands of spars. Wheaten straw thatching, done as here described, will last in our climate for 15-20 years. Oat straw, about 8 years.