Note: Descriptions are shown in the official language in which they were submitted.
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2.
~IWALL-TIES 'I
TECHNICAL FIELD OF THE INVENTION
The invention relates to wa:Ll-ties.
BACKGROUND ART
In timber-frame con~tructioll building~, that iB buildingg
which have an inner timber frame or skin and an outer
brick or,block work ~kin, the timber frame often ~hrink~
with the res~lt that the re]Lative dispositions of the
~ two skins can a,lter, ~ith pos~ible detrimen't to the
;`, stability of the stru,cture or destruction of or deterior-
ation ina ~nish such as plaster. Wall-ties are often
used to try to prevent relative movement. Also~ in
,' brick veneer or masonry cavity walls, it i~ often
', ' necessary *o incorporate a wall-tie or ties in order to
, try to-tie the two skins to~ether. However, proposed
,~ 15 wall-ties have the disadvantage that they provide a
~, bridge ~or moisture condensing in the cavity between
'i the ~kins, ~ith the result th~t conden~ation running
- - - down the inner surface of the outer skin ~trikes the
wàll-tie and flow~ acro3s it to the inner timber frame
or b~ick or block work ~kin which gives rise to dampnes~
of the 'inner ~kin ~ith, again, deterioration in or
destruction of decoration, such as plas*erwork and
' possible warping of the timber frame where this is used.
, F~rther~ore, such proposed wall-tie~ are-~ot flexible
- 25 enough ~o cannot accommodate some relative movemen~-
between the skins~ , , '
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' ' DISCLOSURE OF THE INVENTION
.
, It is an object of the invention to pro~ide a wall-tie
' which ~eeks to overcome the disadvantages of the prior
3 ' wall-ties.
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.~ According *o one a~pect of the invention th~re i8
provided a wall-tie for a multi-skin cavity wall,
comprising a limb for anchorage with one ~kin of the wall,
another limb for anchorage with a skin of the wall
adjacent $he one skin, the limbs being connected together,
" and means for preventing or hindering moisture tran~fer
in usb to the inner skin.
An advantage which may be obtained owing to the invention
; . is that a relatively stiff yet flexible wall-tie i8
obtained which nevertheless does not provide a bridge
or path for moisture, in use, between adjacent skins of
:a multi-skin wall.,
., .
The moisture-preven*ing or hindering means may comprise
one or more downwardly (in use) directed lipsO This is
a relati~ely simple construction which pro~ides a path
- for condensed moisture whereby it can collect at the
lips and condense to drop~ which can then fall dow~ the
- cavity to a ~oisture-de~lecting plate;
The or each lip may be at a lateral edge of the wall-tie~
preferably at a connector, connecting the limbs. This
~ provides a rel~tively simple construc*ion which is
;' relati~ely easy to make.
. The wall-tie may include means to provide enchanced
. stifrness o~ the wall-tie. This enables the wall-tie
to be stiff yet ~lexible to resist compression in a
- . generally horizontal or vertical direction, yet can
- - accommodate torsional flexing while holdin~ adjacent
skins of a cavity wall in which it is installed in
: . desired relative dispositions.
: 30 The stiffness-providing means may comprise a depression,
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which depres~ion ~ be elongate, of U-~hape in cro~-
section and ha~e roundod ends. This is a ~imple yet
ef~ective stifrener and can be incorporated in the wall-
tie in a relatiYely ~imple manner during manufacture.
l . . . .
~ 5 There may be ~eans to enhance the anchor~ge ~f the wall-
;; tie in the wall, and this means may compris~ deformation~
in the limb(s~. The deformations in use grip in ~ortar
between courses of bricks or blocks of a ~kin.
One limb of the wall-tie may lie at substantial~y right
' 10 angles to the other limb, so that in u~e the upright
-, limb may lie along and in contact with the inner skin of
the skins Or the wall, the upright limb being secured
by screws or nails through holes comp~ising the anchorage-
enhancing mean~.
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According to a ~econd a~pect of the invention there i~
pro~ided ~ ~all including a wall-tie as hereinbefore
described.
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Wall-ties embodying *he in~ention are hereinafter described,
`'l by way of example, with reference to the accompanying
~' 20 drawings
,
BRIEF DESCRIPTION OF~THE DRAWINGS
- Fig. l shows a plan ~iew of a first wall-tie;
Fig. 2 shows a longitudinal sectional view of *he
wall-tie of Fig. 1 taksn on the line II-II of ~ig. l;
~ig. 3 shows, to a larger scale, a bot*om plan view
of a second wall-tie;
Fig. 4 shows a side elevation~l view of the wall-tie
of Fig. 3;
Fig. 5 shows a front elevational view of *he wall-tie
~ - . . . . . .
of Figs o 3 and 4;
` Fig. 6 shows~, to a smaller scale t~an that of Fig. 3-5.
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u fragment~ry perspec*ive v:iew of part of a third
w~ tie;
Fig. 7 shows, to a smaller ~cale than that of Figs. 3-5,
. a fragmentary perspective v:iew of a fourth wall-tie;
; 5 Figs~ 8-11 show respecti~ely a perBpective v~ew, plan
view~ side elevational view and underneath plan view Or
a fifth wall-tie7
~igs. 12-16 show respectively a plan view, side elevational
view, underneath plan view, perspective view and end
. elevational view of a sixth wall-tie;
Figs. 17-20 show respectively a perspective view,
underneath plan view, top plan view a~d side elevational
view of a seventh wall-tie;
Figs. 21-25 show respectively a rear perspective view,
a front perspective view, a front elevational ~iew, a
side eievational view and ~ plan view of an eigh~ wall-tie
Figfi. 26-29 show re~pectively a perspective Yiew ~rom in
front, a side elevational view, a front elevational vie
and a bottom plan ~iew of ~ ninth wall-tie;
Figs. 30-32 show the wall-tie of Fig~. 12-15 in use in
a brick or masonry cavi*y wall, Fig. ~0 showing a side
elevational ~iew, ~ig. 31 showing a section in the
direction A-A 9 and ~ig. 3~ showing a perspecti~e vie~
of the wall; ~nd
Figs. 33-35 show the wall-tie of Figs. 26-29 in use in a
timber fra~e wall~ Fig. 33 showing a side elevational
view, Fig. 34 showing a section i~ the direction A-A,
. and ~ig. 35 showing a perspective ~iew of the wall.
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BEST MODES ~OR CARRYIMG OUT THE INVENTION
- 30 Re~erring to the drawings, the wall-ties shown are for
insertion bct~een adjacent skins of a multi-skin briek or
bmberframe cavity wall9particu~arly a cavit~ wall having
an inner and outer skin.. ~igs. 1 and 2 show a wall-tie 1
which is substantially planar, being formed ~ro~ r
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~al~ani~ed mild ~teel and comprising a first part 2,
; for anchoring in one [say the outer) skin of the wall,
and another p~rt 3 for anchoring in the other (the inner)
j~ skin of the w~ll (the skins not baing shown), a
~ 5 connector 4 connecting the two parts 2 and 3, and means
i in the rorm of two lip~ 5 and 6 at the lateral ed$es~ of the connector 4 for preventing or hindering tran~fer
jJ of moisture between the two skins of the wa~l, particularly
from the outer to the inner skin, across the cavity.
The connector 4 al80 has means providing sti~fness of the
wall-tie, in the form of an elongate depression 7 of
U-shape in cross-~ection and having rounded ends which
in use extends abo~e (as viewed)~the ~lane of the parts
2 and 3.
. . ,
TXe lips 5 and 6 each comprise ~ turned down flange
having a ~emi-circular part 8 struck out to provide two
points 9 and 10 at which ~oisture can coalesce to form
, , drople*s whic~ can drop off into the cavity.
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Each part 2 and 3 has a plurality of through holes 10
~; 20 struck through it.
~ 1
The wall tie l is made in one piece from sheet galvanised
-~ ~ mild steel the lips 5 and 6, depression 7 and the holes
~ 10 being formed by suitable metal work-ing machinery
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such as a metal punching and forming machine.
In use, the cavity wall is built up. When it is desired
to strengthen the wall, the wall-tie 1 iB inserted
~; between the skins (not shown) so that the parts 2 and
', 3 lie in a respective skin o~ the wall 7 S~y the inner
" ; and ou*er skin. Mortar-between courses passes through
~ 30 the holes~10 Qnd helps to anchor the wall-tie in positi~n.
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The dimenRions o~ the wall-tie are such that the
connactor 4 lie~ in the cavity. Any moisture condenslng
in the cavity run~ down the lip8 5 and 6 and collects
nt the point~ 9 and 10 in droplets which then drop ,
from *he wall-tie 1 down the cavity to a deflector or
; damp re~istor plate which directR the moisture to the
outside of the wall. The depre~sion 7 acts to stiffen
the wall-tie l.,~nd to r~nder it flexib~e yet ~tiff so'
that it resist~ compres~ion and tension forccs yet can
accommodate torsional changes..
Referring now to Figs. 3-5, the wall-tie 20 shown is
similar to the wall-tie 1 except'that limb 30 lies in
a plane at substantially 90 to the plane of the limb 21.
The limbs'21 and 30 are integral with and connected by
, 15 a connector 22'which includes means 23 for preventing'
. or hindering transfer of mois*ure between the outer and
. inner. skin., and.~ti~fness-providing means. The means 23
comprise, two turned-down lips 24 from each of which a
~ , semi-circular piece of materiai has been removed to
, . 20 provide at each side of the horizontal (as viewed) part
, two point~ 25 and 26 at which moi~ture can coalesce into
drip~.
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The stiffnes-~providing means comprise a depression 27
, which extend~ ,into the (vertical) limb 30.
,
The ,limb 21 has a pluralit~ of circular through holes 28
and the limb 31 has three elongate holes 29.
:
, The wa}l-tie is for use with timber frame construction
'. walls in which there is a *imber.inner frame or wall and
" . ............ an.outër brick or block work wàll separa*ed by a cavi*y.
'. ' ,' , : . .
i! ' 3 ~In use of ~,he wall-tie 20~ the limb 21 is laid ~.inbetween
~, courses- of brick or blo~k work formin~ the outer skin so
that mortar between the course's'passes through the holes 28
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and helps to anchor the wall-tie 20 in the outer ~kin.
Securing de~ice~ ~uch ~8 nail~ or ~cre~ ~re in~erted
through the hole~ 29 into the timber frame, again~t
which the right hand (as viewed) surface of the li~b 30
lie~. The elongate nature of the holes 29 enables the
po~i~ion of *he wall-tie 20 to be adjusted in position
during install~tion, and al~lo enables a vertical movement
o~ the inner ~kin to be accommodated after installation
~hile still maintaining the wall-tie 20 anchored
to the inner skin or timber frame construction. The
depre~sion 27 extends into both limb~ 21 and 30 and i~
of ~-shape in cross-section, has rounded ends and provides
stiffness of the wall-tie 20 while retaining its
flexibility. The wall-tie 20 thus ties the inner and
outer skins *ogetherg particularl~ when the inner timber
frame skin shrink~ 80 maintaining the relati~e
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dispositions o~ the skins, but is flexible ~o that ~light
lateral torsional or ~ertical movements can be accommodated,
BO maintaining the integrity oflth0 structure or fini~h
such a~ plasterwork.
Referri~g now to Fig~. 6 and 7, there is shown anchorage-
snhancing means in the ~orm vf teeth 31 and 32 struck out
from the par~ 2 or 21. The teeth 31, 32 may be used in
either emb~diment described. In Fig. 6 the *eeth -31 protrude
downwardly,as ~iewed,and in Fig. 7 they protrude upwardly
as viewed,at an angle to the plane of the part 2 or 21.
The teeth 31 and 32 are in use embedded in mortar between
courses of`brick or block work ? and help to anchor the
`~ wall-tie 1 or 20 in position. The teeth 31 and 32 are
- 30 struck out in a metal punching or forming op~ration
s ~ during formation of the wall-tie.
~ - Referring now to the embodiment vf Fig~. 8-~1, thè wall-
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tie 4~ ~s ~hown iB ~or u~e in a brick, block or ma~onry
cavity wall. The wall-tie l~o has a p~rt of limb 41
.for insertion in one (say the outer) skin and a part or
limb 42 for inserticn in the other lfiay the inner) ~kin
of the all. The two limbs 41 and 42 are connected by
a connector 43 to provide an integral construct~on. The
two limbs hl and 4Z each taper towards the connector 43
and also turn and curve downwardly to provide lips 44 and
45 each of which haff a semi-circular part struck out to
provide two poin-ts 46 and 47 at which moi6turc can
, coalescc to form droplets which can drop off into the
ca~ity. The lips 44 and 45 are each concave as viewed
~in Fig. 10.
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The wall-tie 40 also has mean~ pro~iding stiffness, in
,~ .15 the form o~ a rai~ed eleme~t 48 o~ U-cross-section which
extends across the connector 43 into each limb 41 and 42
to provide partB 49 of the ele~ent 48 which are narrower
. and lower (Fig. lO) than the element 48. Each limb 41
and 42 has symmetricall~ arranged deformations or
~o depres~ions 50 of. circular shape whish extend or protrude
dcwnwardly ~as viewed in Fig. 10) fro~ the plane o~ each
- limb. The deformations 50 are "b~ind" and thus are in
the form of cups. Each limb 41 and 42 al50 has three
upwardly closed, transYersely extending elongate
.~ 25 de~ormations or dimples 511 of U-shape in cross-section
which extend upwards out of the plane of each limb (Fig. 10).
~ Each deformation.51 is of t~e.same height as the parts 49
" The deformations 51 are staggered with respect to the
deform~tions 50 as considered lëngthwise of the limbs.
.30 I~ use of the wall-tie 40~ the oavity wall is built up
to a desired height. When it is desired to-strengthen
... :. . . .the wall, the wall-tie is laid in place acro~s the
ca~it~ so tha.t the limb 41 is on a bed of mortar o~ the
outer skin a~d the limb 42 is on a bed of mortar of the
inner skin, both ~eds being at the same height. Th~
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connector 43 then lies in the ca~ity with the lips 44 and
45 approximately centrally located in the cavityO The
: wall is then built up, more mortar being placed on the
i limb~ 41 and 42. The deformations 50 an~ 51 be.d into the
5 mortar both abo~e ~nd below the plane of the limbs and provide
a ~ery firm anchor of the wall-tie 4~ in the wall~ The
lips 45 and 46 collect any water which trie~ tD "bridge"
the cavity by running along the wall--tie and so prevents
or hinders ~assage of moisture from the outer to the
; 10 inner skin. The inner skin is therefore protected from
: attack by moisture while at the same tim0 boing tied
to the outer skin. The moisture~collected ultimately
.~ drops off the poin*s 46 and 47.
' ' . ' ' '
. . The element 48, 49 ~cts to stiffen the wall-tie so that
15 it resists compression und tension forces impo~ed on it
~ by movement-of the wall,.particularly.the inner skin
: which tend~ to "settle", whil~ accomm~dating torsional
changes.
The wa~l-tie 60 of Figs~ 12-16 is similar in construction
i 20 and uge to that of.~igs. 8~ o numerals are omitted
_......... for clarity. Th~ main difference~ are that the limbs
. 41 and ~2 o~ the wall-tie 60 have "wavy'l edges, which
enhancç adhesion in the mortar, and the connector 48 is
. narrower than that of Fi~s. 8-11. Importantly, too,
25 the element 48 in the form of means pro~iding stiffnes3
whic~ extends between the two limbs 41 and 42; is of
.. constant cross-section and is raised so that it is
. ~f triangular shape in side elevation (Fig. 14), the apex
61 of the triangle being substantially centrally of the
30 wall-tie, o~er *he points 46 and 47. The narrow ~olded.
.connector enhances the ~trength of the wall-tie 6~, while
. . .the element 48.being raised, also prevents or hinders
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pa~sage of moisture along the length Or the wall-tie,
as an upwardly inclined obstacle i~ presented. Al~o,
the relntive narrowne~s of the connector 48 and
the upwardly direct0d triangular raised element als~
ensure that mortar droppings are not encouraged to
adhere to the wall-tie 60 should they fall onto it from
above when a wall in which the wall-tie is inserted i~
being built. The mortar slide~ off, and BO does not
buil~ up to provide a "bridge" for ~oi~ture. The lateral
~idth of the connector 48 in the wall-tie 60 is less than
the length of the deformatiolls 51.
.
The wall-tie 70 of Figs. 17-20 is also similar in
construction and use to those of Figs. 12-16, so again,
numeral~ are omitted for the purpo~e of cl~rity.
The wall-tie 80 of Figs. 21-25 is for use in a timber
frame wall and i~ similar in construction a~d use to
the wall-tie o~ Figs. 3 and 4. The wall-tie 80 ha~ ~
` part of limb 81 which in u~e i8 secured to a timber frame
of an innsr skin of the wall and a part of limb 82 which
iæ substantially-at 90 to the plane of the limb 81.
The limb 82 is received in u~e in a layer of mortar in
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~,' an outërl brick skin of the wall~ Th~ two limbs 81 and
8~ are integral with and co~nected by a connector 83
which includes means in the form o~ iips 84 and 85
for preventing or hindering transfer of moisture from the
outer skin to the inner skin, and stiffening-praviding
means in the form of a raised channel-shaped element-86.
The two limbs 81 and 82 turn and curve inwardly and
downwardly to form the lips 84 and 85 and each has a
3 curved part struck out to provide two points 87 and-88
(Fig~ ~4) a~ which moi~t~re ~an coalesce into drips.
The stiffness-providing means comprises a channel-shaped
~' element or deformation 86 projectlng forwardLy1 that is
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113~ 77 d~
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to the right a8 ~iewed in ~ig. 22. The deformation 86
extends into both limb~ 81 ~nd 82 i~nd along the
connector 83.
The limb 86 has securing meanR in the form of holes 89
throu~h which pins, screws or the like can be inserted
into the timber frame. The limb 82 has eight symmetrically
.arranged cup-shaped imperforate deformation~ 90 which
- protrude from the plane of the limb o2 in a downward~
direction (Fig. 24). There are also four spaced raised
elongate deformations 91 which extend transversely of the
: length of the limb 82~ The deformations 90 and 91 provide
a firm anchorage of the limb ô2 in a mortar course in
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the outer skin o~ the wall.
.
In use Or the wall-tie.809 the wall is built up to a
requi~ed height and the limb 82 is placed on a bed of
mortar so that the connector.83 spans the cavity and
the rear (to the left as viewed in Fig. 22) surface
. of the limb 81, parallel to and in contac* with the
timber fr~me. Securing means such as nails are then
;, 20 inserted in the hole~ 89 and ~ven m ~ the ti~ber to
sec~re the limb 81 in positionO The ~rick outer skin
~^ i8 the~ built up to th~ required height, the li~b ~2
; being encased in the skin. The deformations 90 and
~ . 91 pro~ide an anchor in the mortar~of the outqr skin.
The eiement 86, which has rounded ends provides
stiffness whilst retaining flexibility, The wall-tie 80
: then ties the inner and outer iskins together, particularly
whea the inner ti~ber frame shrinks, so ~aintainin$
. the relative dispositions of the inner and outer skins 9
i 3 but is.fle~ible so that torsional or ~ertical mo~ements
. can be accommodated, so maintaini~g *he integrity of
the struct~lre and finish such as plasterwork.
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The wall-tie ~00 shown in Figs. 26-29 is al~o for u~e
in timber frame eavity wall~. The wall-tie 100 has a
part or limb 101 for securing to a timber frame inner
~kin and a part or limb 102 for anchoring in a brick
outer skin of A cavity wall. The limb 102 ha~ upward
deformations 103 and downward circular cup-like
deformations 104 (Fig. 27) to enhance anchorage. The
deformations 104 are arranged in two parallel row~ along
the edges of *he limb 102, the de~ormation being
notionally circular in plan and part of the circumference
thereof intercepting the adjacent edge. The two limb~
101 and 102 are connected by a connector 105 comprising
inwardly curved plates or parts 106 which extend in an
initial downward part 107 and then in an upward part 108
between the plane of the limb 102 to the base of the
limb 101 (~ig. 26). A cur~ed part iB struck out of the
parts to provide points 109 and 110 from which moisture
can drip. The upward c~rve 108 of the parts 106
(to the le~t a~ viewed in Fig. 27) prvvides an obstacle
to the passage of moisture fro~ right to left (as viewed,
~ig.26 and Fig. 27). The parts io6 therefore comprise
means to pre~ent or hinder trans~er of moisture from the
outer to the inner ~kin.
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The con~ector 105 also includes an element or deformation
111 which is of channel-3hape in tran6verse cross-section
and which is downwardly open~ in use of the wall-tie 100.
The de~ormation 111 is elongate and has a p~rt 112
extending upwardly (Fig. 27) from the plane of the limb
- 102 at an acute angle to a position intermediatè the
3 length of the deformation 111. A second part 113 continues
to the limb lOlj which it joins at or near its base 11~,
which base 114 is in a plane spaced, in use! above the
plane Or the limb 102. The deformatio~ 111 pro~ides a '
stifrener for the wall-tie 100. In use, if the i~ner
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~kin move~ downwards for whatever reason, such as
shrinkage, this movement can be accommodated by *he
partslll and 112 of the "V" of the deformation moving
together so that the ~ngle at the apex 115 decrea~es.
This movement neYerthele~ m~linta~ ~he upward inclination
of the ~art 112, so pre~enting paYsage of water to the
inner skin. The deformation 111 0tiffen~ the wall-tie
against compre~sional or tensional buckling.
Figs. 30-32 ~how the wall-tie 6 in position t~ tie
together the ~kins of a cavity wall having a brick ve~eer
skin 120 and a blockwork or brick 130 skin separated
by a cavity 140. It can clearly be seen that both
limbs 41 and 42 are embedded in mortar layers in each
skin which are in approximately the same horizontal plane,
and thatthe connector i5 the part of the wall-tie ~hich
;1 i8 exposed in the cavity l40. Fig. 32 shows the wall-tie
laid in place prior to building up the skins of the wall
over it.
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~' Figs. 33-35 show the wall-tie 100 in po~ition to tie
`~ Z0 together the skins of a eavity wall having a brick veneer
outer skin 150 and a timber frame inner ski~ 160, separated
~ by oaYaty 170. The timber frame c~mprises a plurality of
upright ~paced apart and substantially parallel timber
studs 151 to *he eavity side of which is secured a
plywood facing 152(~hich has a moisture membrane 153 on
the c~Yity side). A plasterboard facing 1$4 is secured
to the side of the studs 151 remote from the cavity 170.
: . .
The li~b 102 is anchored in a mortar course of the brick
veneer skin 151, and the limb 101 is secured to a stud
. .
151 by naiI~ or pins inserte~ through the two holes,
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-~ The lips llD6 are clearly seen to be in the caYity.
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15.
In every embodiment~ the limb which is anchored in the
outer skin i~ of sufficient len~th for the hole~ 10
or 28 or deformations to be covered and for the
connector to be clear of the inner surface of the outer
skin~
It will be ~nderstood that the invention above-described
:~ and shown in the accompanying drawings can be modi.fied
in a number ~f ways. .For example, the wall-ties cun be
- made of steel coated ~ith a corrsoion resistor other than
0 R galvanised layer, for example a layer of chlorinated
rubber such as polytetrafluorideethyIene; or the wall-
ties may be made of stainless steel.
Also, in the embodiment of Figs. 3-5, the holes 29
may be circular.
In all the embodiments, the wall-ties are made.in one . -
piece from a single metal ~heet. It ~ill be understood
. - however, thiat the limbsmay be ~nt~ly separate and are
,~. then connected together. '
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~ . It will be appreciated that any downward movement of
.. 20 the inner ~kin which would otherwise tènd to provide a
^ ~lope of the wa~l-tie down~ardly towards that skin is
.
.: ~ . ne~ated in the wall-ties above-described.and shown in the
drawings because the ~ips prevent the tran~fer of
moisture across the cavity to the inner .kin~
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