dangerous area warning sign prohibiting unauthorised people

Construction site security is an important issue for businesses and contractors to consider. When you’re working on a construction project, you want to ensure that it’s secure and inaccessible to trespassers.

An unsecure construction site can be prone to vandalism and theft, which can cause delays and annoyance due to missing or damaged equipment. An unsecure site could be accessed by untrained people, which could lead to injury or death. The prevention of unauthorised access to a construction site must be taken very seriously, and a priority consideration for any construction contractor.

Not only is it unsafe to have unauthorised people on a construction site, but trespassers pose a real risk. They could be thieves, squatters, children, or people attempting to pass through a blocked access route – not every unauthorised person who wants to access your site will have malicious intent or wish to cause trouble. They may be attempting to take a short cut, or simply be unaware that they’re entering a construction site.

Construction site security must be well managed to protect your property, as well as to avoid injury to members of the public.

Here are 20 tips for better construction site security:

construction worker writing on paper

1. Implement a sign in/ sign out procedure

This is an important procedure for every construction site as it allows you to keep an up to date list of people who are present on the site, as well as who isn’t. In cases of emergency, every person on your site needs to be accounted for. At the end of a shift, it also means that you can check everyone has signed out and lock up securely.

2. Use visual ‘authorised person’ identifiers

By using badges, high vis jackets, hard hats, or hard hat stickers you can quickly identify who the authorised personnel are on site. These visual clues let you know who is supposed to be there and who isn’t.

3. Secure the site perimeter

One way in which you can ensure safety on a construction site is through securing the site perimeter with high fencing and blocking any gaps, particularly where the ground below fencing is uneven.

4. Display warning signage

Sometimes a fence is not enough of a deterrent for unauthorised people; it also doesn’t warn people of the dangers. By displaying clear signage, you can ensure people are aware of the dangers, as well as letting them know that their usual routes are currently blocked and inaccessible.

5. Secure and monitor entrances/ exits

If anyone can easily access your construction site, it makes it more prone to trespassing. If you have secure and monitored entry and exit points you can prevent unauthorised visitors gaining access.

6. Explain security procedures to staff and visitors

As part of your staff induction process to the construction site, make sure everyone understands and is aware of the security procedures and controls. This can be from basic security information such as keeping gates locked, barriers remained in place to enforcing security procedures throughout the project.

7. Supervise any visitors

If you have visitors coming onto your site, it is important to ensure they are supervised at all times. Although they are not classed as unauthorised people, they may be unaware of all the different construction site hazards and security procedures.

8. Ask questions to those you suspect are unauthorised persons

Don’t be afraid to ask questions, particularly if you suspect that someone is new or not an authorised person on your site. It could be as simple as a delivery driver struggling to find the main site office, a new employee or contractor, or a friend of the client – it’s always advisable to find out who it is, and why they are on site. If they are not authorised to be on site, you can escort them off the premises.

9. Lock up the premises

Whenever the site is going to be left unoccupied, make sure you lock access gates and secure the premise.

10. Have security patrols and/ or CCTV

If the site is going to be left unoccupied over weekends or holidays, then CCTV or security patrols are needed. 

11. Take extra precautions

Depending on where your construction site is located, particularly if it is in a heavily populated area or within an occupied building, then take extra precautions. You want to make sure the work area is inaccessible.

12. Remove access

If you have any access ladders or scaffolds make sure you remove these out of hours. Ladders and scaffolding can be tempting for people to climb, alongside also not wanting to give unauthorised people an easy access point.

13. Use barriers, corner off dangers

Any excavations on site should be barriered off, or covered to ensure that any potential hazards are reduced. If there is a trespasser accessing the site at night and unaware of where these excavations are, then having a barrier or covering it will ensure added protection and warning.

14. Immobilise all vehicles and plants

If you are leaving the site with vehicles and plant unattended make sure to immobilise the vehicles – never leave keys in equipment or vehicles, this makes it very susceptible to theft, damage and danger.

15. Lock up vehicles and put out of sight

Even after you’ve immobilised and locked any vehicles, to ensure a secure site compound you may also want to put these out of view. If trespassers are looking to steal, you don’t want them noticing your important equipment, tools or materials. Anything that’s tempting for a thief, store it securely and out of sight.

16. Secure hazardous substances

If you have hazardous substances on your site you can place these into secure storage units, making sure it is inaccessible and safely contained.

17. Stack materials safely

You don’t want materials falling or being knocked over, by making sure that these are safely stacked and stored away you ensure that additional bit of safety on a construction site.

18. Check the weather

Depending on the time of year in which you are operating a construction site, it might be worth checking the weather to see if there will be a storm, or bad weather in the area. Wind and rain can cause damage, by making sure that your site is well prepared for this and secure at all times.

19. Maintain your security procedures

When managing construction site security, it is important to maintain procedures. This can include checking the perimeter, fencing and barriers to ensure they are intact and secure.

20. Carry out a risk analysis

This can be done yourselves, or through an external contractor. A risk analysis will help identify potential threats and hazards on the construction site as well as assess the severity and likelihood these could happen. After which, you can then put in measures to reduce or mitigate these.

We hope you found this list of tips for better construction site security helpful.


If you’re interested in construction site security services then you’ve come to the right place, here at TLG Management we specialise in offering and delivering effective and reliable site security. Please don’t hesitate to get in contact with our team by calling 0845 118 0002, or filling out our online contact form and we’ll be in touch.