GB2235009A

GB2235009A - Renovation of structures

Info

Publication number: GB2235009A
Application number: GB8918894A
Authority: GB
Inventors: Ian M Robertson
Original assignee: Channelwood Preservations Ltd
Current assignee: Channelwood Preservations Ltd
Priority date: 1989-08-18
Filing date: 1989-08-18
Publication date: 1991-02-20
Anticipated expiration: 2009-08-18
Also published as: GB2235009B; GB8918894D0

Abstract

Rotten timber support posts in building structures are repaired using a support assembly (1) which is positioned in place of a rotten lower end of post which is removed. The assembly (1) comprises a tubular sleeve (2) having a threaded steel rod (4) which is rotatable therein to achieve vertical movement, by virtue of a bushing (3) disposed within the sleeve. Units comprising a socket (6) and a plate (8) act as a base (10) for the sleeve (2) and as an adaptor (11) for mounting on the threaded rod (4). The plate of the adaptor is raised by turning means applied to the threaded rod (4) (eg by flats 5) so that the plate (8a) abuts the lower face of the sound portion of the post, and thereby render the assembly (1) as a support means to the building, equivalent to that which the post in its original state was designed. <IMAGE>

Description

DESCRIPTION RENOVATION OF STRUCTURES The present invention relates to the renovation of structures incorporating timber support posts which have become rotten.

Timber used in timber framed buildings, such as school buildings, has been found to deteriorate over the years rot usually setting in at the bottom end of the posts which support roof members, the members tending to sag as the posts rot. Repair is then necessary for the building to remain a safe structure.

The usual method of repair involves removal of the entire post and replacement with a new one. The main disadvantage of this technique is the cost of the replacement post when most of the old post is still in good condition. Alternatively cutting out the rotten portion of the post and splicing in a short length of new post is labour intensive and it is necessary to use wedges or the like to jack up the post and compensate for the sag.

It is an object of the present invention to provide a less expensive apparatus and a rapid method for the repair of rotten timber support posts.

According to a first aspect of the present invention, there is provided apparatus for the repair of a rotten timber support post in a building structure, the lower rotten end of the post being removed to leave the sound portion as part of the structure, comprising a support assembly for replacing a rotten lower end of the post, the support assembly having abase and raisable means disposed therein, said means being vertically movable with respect to the base, and an adaptor mountable on the raisable means and securable with respect to the lower end of the post from which the rotten timber has been cut away, the raisable means being vertically adjustable to render the repaired post as effective a support means as the original post when first installed.

Preferably, the support assembly comprises a tubular sleeve housing the raisable means 5 the raisable means being a threaded rod. The rod is rotatable about its longitudinal axis, and thereby vertically movable along this axis by virtue of a corresponding thread on a bushing disposed within the sleeve.

In appropriate circumstances, the tubular sleeve preferably comprises a plurality of extension pieces of tubing.

Preferably, each adaptor and base comprises a receiving socket for the raisable means and a flat plate, the socket further having a flat surface which is adapted to interchangeably receive a plurality of flat plates of various dimensions.

The base and the adaptor are advantageously of identical construction.

Preferably, the receiving socket can rotate about the longitudinal axis of the support assembly.

Conveniently, the rod has means to enable it to be engaged and thereby turned about its longitudinal axis. This may be embodied as flattened portions disposed near an upper end of the rod which can be manipulated with a torque wrench, or as a diametric hole through which a key can be inserted to provide the turning means.

Preferably, the components comprising the support assembly are made of steel.

Provision may be made in the plates for attachment of an inspection cover.

According to a second aspect of the present invention, there is provided a method for repairing a rotten timber post forming part of a building structure, wherein a lower rotten end of the post is removed to leave a sound portion still attached to the structure and wherein an adjustable support assembly is inserted in place of the removed rotten end of the post and the support assembly adjusted until its length corresponds to the length of the removed rotten end, and fixed thereonto in order to render the post in its repaired state as good a support means as the post in its original sound condition.

Preferably, the remaining piece of timber is treated against further rot before fixing onto the support assembly.

By way of example only, a specific embodiment of the present invention will now be described, with reference to the accompanying drawings, in which: Fig.l is an exploded cross-section of an embodiment of an apparatus for the repair of timber posts in accordance with the present invention; Fig.2 illustrates a first stage in the method for repairing timber support posts wherein a rotten lower section of timber post is removed; Fig.3 illustrates a second stage wherein the apparatus in Fig.l is positioned in place of the removed section of timber, and Fig.4 illustrates the apparatus adjusted to the height required to abut the lower section of the remainder of the post.

The support assembly 1 comprises a metal tubular sleeve 2 having a threaded steel bushing 3 fixably disposed therein at the uppermost portion of the sleeve. A threaded steel rod 4 of a diameter smaller than that of the outer sleeve, is threadable into a bushing 3, so that vertical motion along the longitudinal axis of the rod is achievable by clockwise or anti-clockwise turns about this axis. A plurality of flattened portions 5 machined onto the threaded rod 4, enable the rod to be turned, using for example, a torque wrench. A receiving socket 6a comprises a flat plate having a short tubular housing fixable onto this plate, the socket being snugly received over the upper portion of the exposed threaded rod 4. The diameter of this tube is chosen to be less than that of the main sleeve 2.

Fixable onto the receiver socket 6a by means of screws 7 is a head plate 8a, which is of larger width than the socket and which has a peripheral shape matching the cross-section of the post. The socket 6a and plate 8a assembly thus form an adaptor 11.

A support base 10 comprises a socket 6b and a base plate 8b identical to those of the adaptor 11 but receiving the outer sleeve 2 in the reverse direction, the lower end of the sleeve 2 being adapted to flushly fit onto the socket 6b.

With the socket 6a and plate 8a mounted on the rod 4, the threaded rod 4 is then raised by applying the turning means to the flats 5, so that the head plate 8a abuts the free-standing cross-section of the remaining portion of post 10, to which it can be secured with cone-shaped screws or special nails 9.

Furthermore, a variety of head or base plates 8 can be rapidly interchanged and attached according to the specific requirement.

In cases where the base 10 requires mounting on a sole plate 13 which has a stepped profile, packing screws 12 can be adjusted in a vertical direction to maintain the base plate 8b on a horizontal plane.

The apparatus is thus designed to enable the operator to render the repaired post as effective a support as the original post.

Figs. 2 to 4 illustrate an application of the apparatus in the renovation of a timber-framed structure. A timber post 20 is disposed between window frames 21 and is a means of support for flat roof members 24, the base of the post 20 further being mounted on the sole plate 13 which is extended to form a sill. The lower end of the post 20 is shown as having become rotten. In the renovation process, a panel board or capping 25 which may conceal the post 20 is removed to permit examination of the extent of the rot. The rotten portion is then removed, for example by drilling and routing out to leave a sound portion of timber still attached to the roof members 24. The apparatus 1 having head and base plates 8 of dimensions to match the profile of the post, is then positioned in place of the removed rotten end of the post.The screws 12 in the base are adjusted for levelling purposes, to take account of the sole plate 13 which may have a stepped profile. Alternatively, in the absence of the sole plate 13, or if the latter is rotten and needs to be removed, the base 10 can be disposed directly onto underlying concrete. The threaded rod is then manipulated to raise the head plate 8a so that it abuts the lower face of the remaining piece of post, the head plate being secured relative to the post by means of conical screws 9 to prevent the head plate from turning.

The panel board 25 may then be replaced in its original state to conceal the post in its repaired state, or be provided with a small inspection port.

Provision is thus made in all the plates 8 to receive and secure an appropriate length of angled section material, aluminium for example, so that such an inspection port may be closed by a removable cover 26.

The apparatus may be used either way up. That is to say, it may inverted with respect to its position as shown in Figs. 2 to 4, since the plates 8a and 8b are identical.

Claims

1. Apparatus for the repair of a rotten timber post in a building structure, the lower rotten end of the post being removed to leave the sound portion as part of the structure, comprising a support assembly for replacing a rotten lower end of the post, the support assembly having a base and raisable means disposed thereon, which means is vertically movable with respect to the base, and an adaptor mountable on the raisable means and securable with respect to the lower end of the post from which the rotten timber has been cut away, the raisable means being adjustable to enable the support post to be raised to or held at the position for which it was originally designed.

2. Apparatus as claimed in claim 1, wherein the support assembly comprises a tubular sleeve housing said raisable means, the raisable means being a threaded rod.

3. Apparatus as claimed in claim 2, wherein the rod is rotatable about its longitudinal axis and thereby vertically movable along this axis by virtue of a corresponding thread on a bushing disposed within the sleeve.

4. Apparatus as claimed in claim 2 or 3, wherein the rod has means to enable it to be engaged and thereby turned about its longitudinal axis.

5. Apparatus as claimed in claim 4, wherein said engaging and turning means is embodied as either flattened portions near an upper end of the rod to enable the rod to be manipulated with a torque wrench, or as a transverse hole through which a key can be inserted.

6. Apparatus as claimed in any of claims 1 to 5, wherein the tubular sleeve comprises a plurality of extension pieces of tubing.

7. Apparatus as claimed in any of claims 1 to 6, wherein the adaptor and the base each comprise a flat plate and a socket for receiving the raisable means.

8. Apparatus as claimed in any of claims 1 to 7, wherein the base and the adaptor are of identical construction.

9. Apparatus as claimed in claim 7 or 8, wherein said socket has a flat surface which is further adapted to interchangeably receive a plurality of said flat plates of various dimensions.

10. Apparatus as claimed in claim 7, 8 or 9, wherein said socket is rotatable about the longitudinal axis of the support assembly.

11. Apparatus as claimed in any of the preceding claims, wherein said base is provided with screws by which the vertical height of the base can be adjusted.

12. Apparatus as claimed in any of the preceding claims, wherein the base and head plate are further adapted to receive and secure an inspection cover.

13. Apparatus as claimed in any of the preceding claims, wherein the components comprising the support assembly are made of steel.

14. Apparatus for the repair of a rotten timber post forming part of a building structure, substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.

15. A method for repairing a rotten timber post forming part of a building structure, wherein a lower rotten end of the post is removed to leave a sound portion still attached to the structure and wherein an adjustable support assembly is inserted in place of the removed rotten end of the post, and the support assembly is adjusted to render the repaired post as effective a support means as the original post when first installed.

16. A method as claimed in claim 15, wherein the remaining timber is treated against further rot.

17. A method for repairing a rotten timber post forming part of a building structure substantially as hereinbefore described with reference to Figs.2 to 4 of the accompanying drawings.