Stabilisation by needling

Reconstruction targets

Constructive reinforcement of the support structure/ improvement of the transversal tension capability of masonry constructions for the recovery of the fitness for use / conservation of static stability

Reconstruction procedures

Embedding of Ruberstein® Spiral Anchors using Ruberstein® Anchor Grout in bores in transversal direction resp. in direction of the effective transversal forces (needling)

Advantages of the Ruberstein® Spiral Anchor System

  • Effective reinforcement with high bonding action in almost all wall materials
  • Little invasion into the building structure; application possible even on sensitive surfaces
  • Simple processing, no heavy machinery necessary
  • Easy storage and transport
  • Delivery on rolls - no material loss due to cutting scrap

Construction rules

  • Anchor diameter preferably Ø 10 mm or Ø 12 mm, smaller diameters are possible depending on the application
  • Anchor length according to static requirements, however ≥ 100 mm
  • Number/arrangement of anchors ≥ 2,5 anchors per m², if not specified otherwise,

    dhorizontal ≤ 900 mm, dvertical ≤ 450 mm

  • Bore diameter depending on anchor diameter at least 12, 14, 16 or 20 mm


Material and accessories

Ruberstein® Spiral Anchors, type Standard (without tip)

Ruberstein® Anchor grout

Commercially available hammer drill

Mortar gun (with filling tube), if necessary pneumatic or spiral pump


Video stabilisation by needling


  1. Prepare a bore in the masonry
  2. ‚Blow out the bore, moisten with water
  3. ƒCut the spiral anchor to length and prepare the anchor grout

  4. „Press the anchor grout into the bore

  5. Turn in the spiral anchor straight into the fresh grout

  6. Close the wall surface with anchor grout, joint mortar or stone restauration mortar


  Bore diameter d
12 mm14 mm16 mm18 mm20 mm22 mm
Consumption per m 0,11 l 0,15 l 0,20 l 0,25 l 0,31 l 0,38 l
Yield per bucket (6 l) ≈ 53 m ≈ 39 m ≈ 30 m ≈ 24 m ≈ 19 m ≈ 16 m


Consumption / yield of the Ruberstein® Anchor Grout (anchor volume neglected)


 Main areas of application

- Reinforcement / stabilisation of natural stone walls and thick brick walls

- Crack needling (cross-wise) in thick wall constructions

- Stabilisation and load carrying capability increase of arched constructions

- Securing of decorative / design elements