HTT

Hold Down

Ideal for existing or new construction, HTT Tension ties provide a high strength timber to concrete, or timber to masonry, tension connection

The long vertical leg makes it possible to add the required number of fasteners (CNA Nails and CSA Screws) in a vertical post and still comply to relevant standards with regards to fastener spacing requirements.

The unique design of the HTT - a multi ply seat formed from a single piece of steel - gives the tension tie extra strength at the concrete / masonry anchorage point

Technical Data Sheet

CE Marking

ETA

Service class 2

Electrogalvanized steel 20 µm

Indoor

Product Details

Images

Features

Material

Z275 Pre-galvanised mild steel.

Benefits

Enables a connection to concrete structure.

Application

Connections

Timber Members

When to Use

Timber structures which exerted to high uplift forces can be connected to concrete structures with the HTT Hold Down.
Tension force connection between timber floor joists and masonry walls

Technical Data

Dimensions

Product Dimensions

References	DB nr.	NOBB nr.	Product Dimensions [mm]						Flange A			Flange B			Box Quantity
References	DB nr.	NOBB nr.	A	B	C	D	E	t	Ø4,7	Ø5	Ø21	Ø17,5	Ø18	Ø25	Box Quantity
HTT4	1388657	42922721	314	60	64	11.4	35	2.8	18	-	-	1	-	-	16
HTT5	1388655	42922755	403	56	64	11.4	35	2.8	26	-	-	1	-	-	10
HTT22E	2049836	-	558	60	63	12	33	3	-	31	3	-	1	-	10
HTT31	2151752	-	790	60	90	12	33	3	-	41	6	-	-	1	5

Capacities

References	Number of Fasteners				Characteristic capacities - Timber C24 to concrete [kN]
	Joist		Flange B		R_1.k(without US50/50/8 washer)								R_1,k (with US50/50/8 washer)
	Qty	Type	Qty	Type	CNA4,0x35	CNA4,0x40	CNA4,0x50	CNA4,0x60	CSA5,0x35	CSA5,0x40	CSA5,0x50	CSA5,0x80	CNA4,0x35	CNA4,0x40	CNA4,0x50	CNA4,0x60
HTT4	n	CNA	1	M16	min [(n-3.5)*1.66; 15.4; 43/kmod]	min [(n-3.5)*1.83; 18.6; 43/kmod]	min [(n-3.5)*2.22; 24.7; 43/kmod]	min [(n-3.5)*2.36; 31; 43/kmod]	-	-	-	-	min [(n-3.5)*1.66; 19.7]	min [(n-3.5)*1.83; 23.9]	min [(n-3.5)*2.22; 31.7]	min [(n-3.5)*2.36; 39.7]
HTT5	n	CNA	1	M16	min [(n-3.5)*1.66; 15.4; 43/kmod]	min [(n-3.5)*1.83; 18.6; 43/kmod]	min [(n-3.5)*2.22; 24.7; 43/kmod]	min [(n-3.5)*2.36; 31; 43/kmod]	-	-	-	-	min [(n-3.5)*1.66; 19.7]	min [(n-3.5)*1.83; 23.9]	min [(n-3.5)*2.22; 31.7]	min [(n-3.5)*2.36; 39.7]
HTT22E	n (1)	CNA/CSA	1	M16	min [(n-3,5)*1,66; 32,6; 57,5/kmod]	min [(n-3,5)*1,83; 39,6; 57,5/kmod]	min [(n-3,5)*2,22; 42,3; 57,5/kmod]	min [(n-3,5)*2,36; 53,1; 57,5/kmod]	min [(n-3.5)*1,99; 91,1; 57,5/kmod]	min [(n-3.5)*2,25; 106,7; 57,5/kmod]	min [(n-3.5)*2,63; 138,2; 57,5/kmod]	min [(n-3.5)*3,5; 232,4; 57,5/kmod]	-	-	-	-
HTT31	n (2)	CNA/CSA	1	M24	min [(n-4)*1,66; 144,1; 85,1/kmod)	min [(n-4)*1,83; 144,1; 85,1/kmod)	min [(n-4)*2,22; 144,1; 85,1/kmod)	min [(n-4)*2,36; 144,1; 85,1/kmod)	min [(n-4)*1,99; 144,1; 85,1/kmod)	min [(n-4)*2,25; 144,1; 85,1/kmod)	min [(n-4)*2,63; 144,1; 85,1/kmod)	min [(n-4)*3,5; 144,1; 85,1/kmod)	-	-	-	-

Quantity of fasteners (n) may be choosen by the user. Capacity is then calculated with this number n.
⁽¹⁾ n is equal to 10 a maximum.
⁽²⁾ 4 CSA5.0x80 must always be installed on the bottom extremity of the oblong holes to reach the capacities given in the table. For other fastener in these 4 holes, the capacaity shall be calculated according to ETA.

Product capacities - simplified values

References	Product capacities - Timber to Concrete
	Number of Fasteners				Characteristic capacities - Timber C24 to concrete [kN]
	Flange A		Flange B		R_1.k(without US50/50/8 washer)								R_1.k (With US50/50/8 washer)
	Qty	Type	Qty	Type	CNA4.0x35	CNA4.0x40	CNA4.0x50	CNA4.0x60	CSA5.0x35	CSA5.0x40	CSA5.0x50	CSA5.0x80	CNA4.0x35	CNA4.0x40	CNA4.0x50	CNA4.0x60
HTT4	18	CNA	1	M16	15.4	18.6	24.7	31	-	-	-	-	19.7	23.9	31.7	34.2
HTT5	18	CNA	1	M16	15.4	18.6	24.7	31	-	-	-	-	19.7	23.9	31.7	34.2
HTT22E	26	CNA/CSA	1	M16	32.6	39.6	42.3	52.3	44.8	50.6	52.3	52.3	-	-	-	-
HTT31	39	CNA/CSA	1	M24	58.1	64.1	77.4	77.4	69.7	77.4	77.4	77.4	-	-	-	-

Simplified numerical characteristic capacities values are based on load duration and service class assumption (Instantaneous, Service class 2, k_mod = 1.1). For other load duration, service class and fasteners, please refer to ETA-07/0285.

For HTT31, 4 CSA5.0x50 must always be installed on the bottom extremity of the oblong holes to reach the capacities given in the table. For other fasteners in these holes, the calculation shall be calculated according to ETA.

Product capacities with Zyklop, simplified

References	Product capacities with ZYKT [kN]
	Fastener						Characteristic capacities - Timber C24 to concrete [kN]
	Flange A				Flange B		R_1.k
	Qty	Type	Qty	Type	Qty	Type	R_1.k
HTT4	-	-	-	-	-	-	-
HTT5	-	-	-	-	-	-	-
HTT22E	-	-	-	-	-	-	-
HTT31	-	-	-	-	-	-	-

The capacities for the ZYKT69 are determine for an embendingth length of the screws of the ZYKT of 280 mm. Details of the Zyklop are givne in ETA-07/0317.

The essential CNA / CSA have to be place in the oblong holes (lower side), and for the HTT22E also in the 2 lowermost holes Ø5 mm.

Installation

Fixing

Fastening into Timber Stud:

4mm CNA Nails
5mm CSA Screws

Fastening to the concrete:

Mechanical anchors: M16 WA Anchor or BOAX-II
Chemical anchors: injection mortar SET-XP or AT-HP + M16 threaded rod LMAS

Installation

The connector is mounted with a suitable M16 bolt to the concrete or masonry wall, and the vertical leg is fastened with 4mm CNA Nails, or 5.0mm CSA Screws, to the timber.