Through bolts are heavy-duty mechanical fasteners designed to create secure, permanent fixings in solid base materials such as concrete, brick, and stone. Unlike expansion anchors that grip within a pre-drilled hole, through bolts pass completely through the fixture being mounted and anchor into the base material behind, providing exceptional load-bearing capacity and reliability. MyToolShed.co.uk stocks a comprehensive range of through bolts from Rawlplug, a trusted name in professional fixings, available in various materials including zinc plated, hot-dip galvanised, and A4 stainless steel finishes.

These versatile fasteners consist of a threaded bolt with an expansion sleeve that compresses against the sides of the drilled hole when tightened, creating a secure mechanical lock. Through bolts are essential for applications requiring maximum strength and safety, particularly where heavy loads, vibration, or critical structural connections are involved. The range at MyToolShed.co.uk includes specialist options such as wire hanger through bolts with eye bolts for suspended installations.

Applications

Through bolts are widely used across various trades and industries for demanding fixing applications:

Construction and structural engineering: securing steel beams, brackets, and structural connections to concrete
Mechanical and electrical installations: mounting heavy machinery, motors, cable trays, and distribution boards
HVAC contractors: fixing air conditioning units, ventilation equipment, and ducting supports
Shopfitting and commercial installations: anchoring racking systems, security barriers, and suspended ceilings
Civil engineering: infrastructure projects, bridge components, and safety barriers
Industrial maintenance: equipment mounting in factories and warehouses
Suspended services: installing pipework, cable management systems, and overhead fixtures

Choosing The Right Through Bolts

Selecting the appropriate through bolt requires careful consideration of several factors:

Base material: Ensure the through bolt is rated for your substrate (concrete, brick, or stone) and check the minimum embedment depth required
Load requirements: Calculate the working load including safety factors, and verify the bolt's rated capacity for tension and shear forces
Environmental conditions: Choose zinc plated for internal dry applications, hot-dip galvanised for external or damp environments, and A4 stainless steel for corrosive or marine conditions
Diameter and length: Select based on fixture thickness and required embedment depth into the base material
Installation type: Consider specialist options like eye bolt variants for suspended installations or standard hex head for general mounting
Standards compliance: Verify the through bolts meet relevant BS/EN standards and building regulations for your application

Safety Information

Always drill holes to the exact diameter specified by the manufacturer, as undersized or oversized holes compromise holding strength. Ensure minimum edge distances and spacing between fixings are maintained to prevent concrete breakout. Use appropriate personal protective equipment including safety glasses and dust masks when drilling. For structural or safety-critical applications, installations should be designed by a qualified engineer and inspected upon completion. Never exceed the manufacturer's stated working load limits.

Frequently Asked Questions

What's the difference between through bolts and other anchor bolts?
Through bolts pass completely through the fixture being mounted and anchor into the base material, providing superior holding power compared to expansion anchors. They're ideal for heavy-duty applications requiring maximum strength and reliability.

Can through bolts be removed and reused?
While through bolts can technically be removed, they're designed as permanent fixings. Removal may damage the expansion mechanism, and the bolt should not be reused in structural applications. Always install a new through bolt for critical fixings.

Which material finish should I choose?
Use zinc plated for internal dry environments, hot-dip galvanised for outdoor or damp locations, and A4 stainless steel for coastal, marine, or highly corrosive environments where maximum corrosion resistance is required.