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PAI/MPAI Purlin Anchors

PAI/MPAI

Straps and Anchors for I-Joists

This product's information may differ depending on the category of use. You are currently viewing details related to Straps and Anchors for I-Joists. You can also view product information related to the category: Purlin Anchors

Wood-to-concrete and wood-to-CMU connectors that satisfy code requirements for wind and seismic design categories (SDC) A-F. The PA's dual embedment line allows installation in concrete or CMU wall. The PAI and MPAI are code listed under the 2009 and 2012 IBC and IRC ESR-2920 and have been tested to meet the requirements of ICC-ES acceptance criteria AC-398 for cracked and un-cracked concrete.

Material

  • MPAI — 14 gauge; PAI — 12 gauge

Finish

  • Galvanized.

Installation

  • Use all specified fasteners; some models have extra fastener holes. See General Notes.
  • Purlin anchor must hook around rebar (ASCE7-10 12.11.2.2.5).
  • Allowable loads are for a horizontal installation into the side of a concrete or CMU wall.
  • Strap may be bent one full cycle. (Bent vertical 90° then bent horizontal.)

Edge Distance: Minimum concrete edge distance is 5". Minimum CMU wall left-to-right edge distance is 20".

Concrete CMU Walls: The minimum wall specifications are:

AOne # 4 vertical rebar, 32" long, 16" each side of anchor
B — Two courses of grout-filled block above and below the anchor (no cold joints allowed)
CA horizontal bond beam with two #4 rebars, 40" long, a maximum of two courses above or below the anchor
DMinimum CMU compressive strength, f'm = 1,500 psi

Options

  • See LTT and HTT tension ties for alternate retrofit solutions.

Related Literature

Load Tables

    These products are available with additional corrosion protection. Additional products on this page may also be available with this option, check with Simpson Strong-Tie for details.

Wind and SDC A&B — Allowable Tension Loads (160)
Max. Ledger Size Model No. Strap Length, L (in.) Embed Length, le (in.) Non-Cracked Concrete Cracked Concrete GFCMU Wall Max. Allowable Strap Tensile Capacity Deflection at Allowable Load (in.)
Concrete GFCMU Required Nails Tension Required Nails Tension Required Nails Tension
4x Ledger PAI18 18 1/2 4 6 (9) 10d x 1 1/2" 1,820 (9) 10d x 1 1/2" 1,820 (9) 10d x 1 1/2" 1,055 NA 0.100
PAI23 23 3/4 4 6 (14) 10d x 1 1/2" 2,835 (14) 10d x 1 1/2" 2,360 (14) 10d x 1 1/2" 1,805 NA 0.158
PAI28 29 4 6 (16) 10d x 1 1/2" 3,370 (16) 10d x 1 1/2" 2,360 (16) 10d x 1 1/2" 2,705 NA 0.167
PAI35 35 4 6 (18) 10d x 1 1/2" 3,370 (18) 10d x 1 1/2" 2,360 (18) 10d x 1 1/2" 2,815 NA 0.130
MPAI32 32 5 1/2 (16) 10d x 1 1/2" 2,335 (16) 10d x 1 1/2" 2,355 NA 0.167
MPAI44 44 5 1/2 (24) 10d x 1 1/2" 2,865 (24) 10d x 1 1/2" 2,865 NA 0.167

See Footnotes1 below

SDC C–F — Allowable Tension Loads (160)
Max. Ledger Size Model No. Strap Length, L (in.) Embed Length, le (in.) Non-Cracked Concrete Cracked Concrete GFCMU Wall Max. Allowable Strap Tensile Capacity Deflection at Allowable Load (in.)
Concrete GFCMU Required Nails Tension Required Nails Tension Required Nails Tension
4x Ledger PAI18 18 1/2 4 6 (9) 10d x 1 1/2" 1,820 (9) 10d x 1 1/2" 1,820 (9) 10d x 1 1/2" 1,055 4,180 0.100
PAI23 23 3/4 4 6 (14) 10d x 1 1/2" 2,830 (14) 10d x 1 1/2" 1,980 (14) 10d x 1 1/2" 1,805 4,180 0.158
PAI28 29 4 6 (20) 10d x 1 1/2" 2,830 (16) 10d x 1 1/2" 1,980 (16) 10d x 1 1/2" 2,705 5,070 0.167
PAI35 35 4 6 (20) 10d x 1 1/2" 2,830 (18) 10d x 1 1/2" 1,980 (18) 10d x 1 1/2" 2,815 5,070 0.130
MPAI32 32 5 1/2 (16) 10d x 1 1/2" 2,355 3,205 0.167
MPAI44 44 5 1/2 (24) 10d x 1 1/2" 2,865 3,205 0.167

Footnotes1

  1. Allowable loads have been increased for earthquake or wind load durations with no further increase allowed.
  2. Deflection listed is at highest allowable load.
  3. To obtain LRFD values for purlin anchors, multiply ASD seismic load values by 1.4 and wind load values by 1.6 (1.67 for 2015 IBC).
  4. Minimum center-to-center spacing is 3x the required embedment. Standard installation is based on a minimum 5" end distance.
  5. For wall anchorage systems in SDC C-F, the maximum allowable strap tensile capacity shall not be less than 1.4 times the ASD anchor design load.
  6. Nail quantities are based on Douglas Fir (DF) or equivalent specific gravity of 0.50 or better. For use in Spruce-Pine-Fir (SPF) or Hem Fir (HF) nails quantities shall be increased by 1.15 to achieve loads listed.
  7. Structural composite lumber beams have sides that show either the wide face or the lumber strands/veneers. Values in the tables reflect installation into the wide face.
  8. Concrete shall have a minimum concrete strength, f'c of 3,000 psi. Minimum f'm = 1,500 psi for masonry.
  9. For PAI/MPAI models, 10d x 1 1/2" nails shall be used directly onto framing member. For installation over sheathing, use 2 1/8" long nails minimum.
  10. Nails: 10d = 0.148" dia. x 3" long, 10d x 1 1/2" = 0.148" dia. x 1 1/2" long.
    See other nail sizes and information.

Code Reports

Part IAPMO UES ER ICC-ES ESR City of Los Angeles State of Florida
MPAISee specific model numbers for code listings.
MPAI32No code listing: Please contact us for test data.
MPAI44No code listing: Please contact us for test data.
PAISee specific model numbers for code listings.
PAI18 ESR-2920 ESR-2523 FL13326
PAI23 ESR-2920 ESR-2523 FL13326
PAI28 ESR-2920 ESR-2523 FL13326
PAI35 ESR-2920 ESR-2523 FL13326

ESR-2523 is an Index of many of Simpson Strong-Tie Stamped and Welded Cold-formed Steel Products for Wood or Cold-formed Steel Construction

Drawings

Part Orthographic Perspective
MPAINone None
MPAI32None None
MPAI44None None
PAINone
PAI
DWG DXF
PAI18
PAI18
DWGDXF
PAI18 front view
DWG DXF
PAI18 left view
DWG DXF
PAI18 right view
DWG DXF
None
PAI23
PAI23
DWGDXF
PAI23 front view
DWG DXF
PAI23 left view
DWG DXF
PAI23 right view
DWG DXF
None
PAI28
PAI28
DWGDXF
PAI28 front view
DWG DXF
PAI28 left view
DWG DXF
PAI28 right view
DWG DXF
None
PAI35
PAI35
DWGDXF
PAI35 front view
DWG DXF
PAI35 left view
DWG DXF
PAI35 right view
DWG DXF
None