GB2482790A - Timber or timber substitute blocks for use in massive timber structure - Google Patents

Abstract

The blocks 11 comprise inter-engaging features such that they can be formed into a larger building structure. The blocks preferably include a tongue 12 and groove 13 formation for co-operative engagement with similar adjacent blocks. The tongue and groove may each respectively comprise a barb 12a and rebate 13a which elastically deform when the blocks are pressed together before locking together. The blocks may be secured together mechanically or by using an adhesive. The blocks are preferably used to form a structure such as a wall in a building, the wall being attached to the building via brackets attached to support structures within the building. The blocks can also be used to form columns, beams and door frames and are preferably sized similarly to conventional building blocks, such as bricks. Also claimed is a laminated structure comprising two layers of block panels secured together. The timber substitute may be plastic, chipboard, acrylic or metal.

Description

Building This invention relates to massive timber and to buildings and other structures made therefrom.

Massive timber is discussed in a dissertation "Massive Timber, Why Aren't We Using It More?" by Anton Balchin, BSc (Hons) Architectural Studies, University of Strathclyde, Glasgow (http liaichin ni uk fiLs 201 0 02 f)is'.crtation\Vb pdt) This dissertation notes that massive timber results from merging the technologies developed during the forming of wood based boards, such as blockboard, traditional log construction, and the bonding of Glu-Lam to create out of timber pieces a structural timber system consisting of one solid element, providing both the load bearing and internal finish for a building. It requires, much like timber panel preparation, industrial manufacturing, large workshops and special tools, in which the timber pieces are assembled and bonded together by dowelling and/or glue.

As the name implies, the individual elements are large, up to 1 8m in length, and they are made in correspondingly dimensioned machines A limitation on size is transportation from factory to building site, though even larger elements can be made by joining two or more massive timber elements together. Among advantages of massive timber are quality and cost control because of fabrication in the controlled factory environment, and little exposure to the elements prior to construction.

However, the cost of transportation is a significant factor, and increases with distance, detracting from the otherwise favourable environmental impact of building in timber..

The capital cost involved in manufacture is such that factories are few and far between, and only a few manufacturers have invested.

Moreover, some timbers arc prone to warping, particularly faster growing species, and are unsuitable on that account for making massive structures.

The present invention utilises the concept of massive timber, and retains the advantages, but eliminates disadvantages enumerated above. it facilitates novel buildings, and methods for constructing them, as well as new building components, that facilitate building using solid timber technology, while enabling lower capital cost manufacture and facilitating the use of lower grade timbers and even timber substitutes.

The invention comprises timber or timber substitute blocks adapted for assembly into a composite massive building element, the blocks having interengaging features facilitating firm filling manual assembly one with another such as to be mutually tensioned when engaged whereby mating faces engage with mutual pressure.

The blocks may have tongue and groove interengaging features, which may be barbed or otherwise profiled for mutually tensioned interengagement.

The mutual tension may arise from elastic deformation of the tongue and groove features as the blocks are assembled. Assembly may be assisted by malleting or pressing. The mutual tension may be such as will serve without further measures to bind the massive timber element together as well as the components of conventional massive timber elements, but may be at least sufficient to clamp the blocks together for glue to set.

The blocks may be monolithic or may themselves be made from smaller timber pieces, as mini-massive timber elements, when they might be glued or dowelled, perhaps with expanding dowels, or other mechanical assembly. Monolithic blocks may be cut from a round log or a quarter-sawn log.

The blocks may, in particular, have a groove on one face, which may extend parallel to the long edge of the face and which may bisect the face, and a corresponding tongue on the opposite face. The tongue and groove may, in cross-section, be trapezoidal, with inclined sides each containing a barb arrangement. A symmetric arrangement facilitates construction inasmuch as orientation is not required. However, asymmetric arrangements are possible and may have advantages in some circumstances.

The blocks may be of the same order of size as conventional house bricks and masonry, which is to say ranging from 200 x 100 x 50mm up to 900 x 250 x 400, so that they can be laid' by hand, as with conventional clay, stone and like material bricks and blocks.

Blocks in these sizes can be made from faster growing, and therefore less expensive, C16 timber, which is more prone to warping than the timbers usually used in massive timber.

The blocks can be assembled into a warp-free massive timber panel of much larger dimension, which, if monolithic, or made from longer members, would be prone to warping such as would render it unsuitable for building construction. It is thought that C16 timber in shorter lengths is not so prone to warping as in longer lengths, but, in any event, the interengagement of shorter lengths will cancel out any tendency to warp.

There is, of course, no reason why more expensive timbers used in conventional massive timber products cannot be used.

Blocks of timber substitute may, as suggested above, be used. By timber substitute' is meant any material, such as plastic, which may be fibre reinforced, with properties such as density, elasticity, durability, resistance to elemental attack, thermal conductivity, strength in tension and/or compression akin to wood, along with the ability to be worked, drilled, sawn and bonded, for domestic or comniercial buildings or such other properties as may be apposite to any other use to which the blocks may be put, as in retaining walls, bridges and so forth. Timber and timber substitute may be inherently, or may be formulated or treated to be, fire resistant The invention also comprises panels and other structural members assembled from such blocks, as well as a building or other structure incorporating at least one such panel or member.

The invention also comprises a method of making a massive timber element comprising assembling timber or timber substitute blocks having interengaging features facilitating firm filling manual assembly one with another such as to be mutually tensioned when engaged whereby mating faces engage with mutual pressure.

The blocks may be assembled without gluing, relying on the mutual tension to hold them firmly in place, or with gluing, relying on the mutual tension to clamp them while the glue sets.

The panel or other structural member may be a load-bearing member, such as a beam, a column or a wall, or an infill mcmber, for example, for a frame, e.g. a timber frame building, for example a building constructed according to 0B2404205 or 0B24 18437, which disclose rib frame structures for buildings.

The panel or other structural member may be assembled in situ, in the manner of building using brick or stone, or may be factory assembled and transported to a building site for assembly with other building components. The blocks may be assembled using bricking bonds such as Stretcher, English and Flemish bond.

Assembled panels may be connected to structural or frame members by brackets, which may be slotted to allow for relative movement -panels and other structural members according to the invention may, like conventional massive timber panels, expand and contract with changes in ambient relative humidity and temperature.

Blocks, panels and other structural members, buildings and methods for assembling and constructing them according to the invention will now be described with reference to the accompanying drawings, in which: Figure 1 is a cross section of two blocks assembled together; Figure 2 is a detail of Figure 1; Figure 3 is a plan view of the block of Figures 1 and 2; Figure 4 is a side elevation of the block of Figures 1 to 3; Figure 5 is a cross section of a block showing a first cuffing pattern; Figure 6 is a cross section of another embodiment of block, showing a different cutting pattern; Figure 7 is a view of a partly-assembled freestanding wall comprising first embodiment blocks; Figure 8 is a view like Figure 7 of a partially assembled wall comprising blocks stack bonded between structural members; Figure 9 is a view like Figure 7 of a partially assembled wall comprising blocks stack bonded to form a face on structural members; Figure 10 is a perspective view of a beam assembled from blocks illustrated in Figures 1 to 5; Figure 11 is a perspective view of a first embodiment of column; Figure 12 is a view like Figure 11 of a second embodiment of column; Figure 13 is a perspective view of a portal frame; Figure 14 is a perspective view of a first laminated structure; Figure 15 is a view like Figure 14 of a second laminated structure The drawings illustrate timber or timber substitute blocks 11 adapted for assembly into a composite massive building element, the blocks having interengaging features 12, 13 facilitating firm fitting manual assembly one with another such as to be mutually tensioned when engaged whereby mating faces 14, 15 engage with mutual pressure.

The blocks 11 themselves may be of wood and monolithic or assembled from small timber pieces as by adhesive bonding or expanding dowelling or other mechanical assembly. They may be of a timber substitute, such as blockboard, chipboard, plastic, such as acrylic plastic, which may be fibre or otherwise reinforced, and even of metal.

The blocks 11 have tongue 12 and groove 13 interlocking. The tongue 12 has a barb 12a -see particularly Figure 2 -and the groove 13 has a rebate 13a for retaining the barb 12a when interlocked. The dimensions of the barb 12a and recess 13a are such that the block 11 can deform elastically for engagement. The tongue 12 is of lesser depth than the groove 13, whereby to permit engagement of the barb 12a and recess 13a by forcing the tongue 12 into the groove 13, as by malleting.

The tongue and groove arrangement may facilitate adhesive-free assembly, by the barb and recess feature holding the components together with good mutual intersurface pressure -which may desirably, depending on the application, be at least such as to militate against the tongue 12 sliding in the groove 13. However, bonding may be reinforced by gluing, the tongue and groove-induced tension being at least sufficient to hold the blocks together while an adhesive sets.

The groove 13 extends parallel to the long edge 1 la of the face 1 lb of the block 11 bisecting the face lib, the tongue 12 being correspondingly arranged on the opposite face llc. The tongue 12 and groove 13 of the embodiment of Figures 1 to 5 are, in cross-section, trapezoidal.

Figure 5 illustrates a cuffing paffern for the block 11 from a quarter-sawn log 51. Figure 6 illustrates a cuffing paffern for the block 11 from a round log 61. Tn this block 11, the tongue 12 is cleft at 62 for ease of insertion into the groove.

S It is possible to make the blocks 11 to any desired dimensions, for example, to aid wall stability or strength, or to create particular visual effects when used as facings. It is possible, moreover, to use bricks of different sizes in the same panel or other building elements, so long as they fit together.

The tongue and groove interlocking illustrated in Figures 1 to 6 is robust and straightforward to implement and use, but other interlocking arrangements can be used instead. While a panel or wall made of the blocks 11 as illustrated may, depending on the tightness of fit, be disassembled, provided glue has not been used to strengthen the bond or make a permanent bond, by relative sliding until the tongue comes out of the end of the groove, other interlocking arrangements may facilitate simply lifting the tongue out of the groove, or a push-to-engage, push-to-disengage arrangement might also be used.

Figure 7 illustrates a freestanding wall 16 in the course of construction by assembling blocks 11 in stretcher bond. Such a wall may be a load-bearing wall. Other bricking bonds may be used instead of Stretcher bond, e.g. Flemish or English bond.

Figures 8 and 9 illustrate stack-bonded units forming panels 17, 18 supported by structural members 19. Figure 8 illustrates infill panels 17 held by brackets 21 behveen structural members 19, while Figure 9 illustrates panels 18 used as facing to the structural members 19. The wall and the panels 17, 18 may be assembled in situ, which involves locating a first block 11 to a frame member and then building the panelling block by block relative to the structural members. Or the panelling may be factory assembled and fiffed to the structural members on site. The blocks may be assembled into panelling using bricking bonds such as Stretcher, English and Flemish bond or by stack bonding as illustrated.

The blocks 11 are of the same order of size as conventional house bricks, which is to say ranging from 200 x 100 x 50mm up to 900 x 250 x 400, so that they can be laid' by hand, as with conventional clay, stone and like material bricks and blocks. Blocks in these sizes can be made from faster growing Cl 6 timber, which is prone to warping at longer lengths, and assembled into a warp-free massive timber panel of much larger dimension which, if monolithic, or made from longer members, would be prone to warping such that would render it unsuitable for building construction.

Figure 10 illustrates a beam 101 assembled from blocks 11. Figures 11 and 12 illustrate columns 111, l2lalso made of blocks 11. The column of Figure 11 is a simple stack of blocks 11 one on top of another, while the column of Figure 12 has the blocks 11 arranged in a brick bond, much like the beam 101 of Figure 10 turned on its end.

Figure 13 illustrates a portal frame 131 made, again, of blocks 11.

Figures 14 and 15 illustrate laminated structures 141, 151 respectively. Figure 14 shows a structure comprising front and rear wall panels 141a, 141b, bonded, e.g. adhesively, to an intermediate layer of a substance such as plywood, oriented strand board or a metal such as steel that is dimensionally stable notwithstanding variations in atmospheric S temperature or humidity.. Figure 15 shows a structure formed from the layers 151 a, iSib, lSlc, of block panel bonded, again, for example, adhesively, with the grain' of the middle panel iSib being orthogonal to the grain of the outer panels iSla and iSle The structural members can take the place of conventional columns, beams, joists, panels and infill, and can be used in place of all conventional massive timber building elements.

They can also be part of a timber rib frame construction as disclosed in GB2404205 or 0B2418437, in which the panelling is assembled from the blocks 11 to fill between the rib frame members.

By virtue of the invention herein disclosed, massive timber panels or other building elements can be constructed without the correspondingly massive machinery conventionally required.