The Cost of Ambiguity in Perimeter Security Tenders

When drawings, specifications and tender information don't quite agree, contractors aren't pricing the same perimeter package. They're pricing different interpretations of it… and that's where cost, delay and security risk begin.

This is what we describe as the Security Intent Gap: the distance between what the client believes they have asked for and what the project information actually tells the market to price.

Missing dimensions on a layout drawing

A perimeter security drawing doesn't have to be wrong to cause a problem. It just has to be open to more than one reading.

Where a drawing and specification don't fully agree, or a detail is left unstated, tenderers aren't pricing the same package. They're pricing their own assumptions. That doesn't produce five prices for the same solution. It can produce five different solutions, all sitting underneath the same BOQ line.

If the dimensions aren't stated, every tenderer has to make an assumption. One measures 5 metres, another assumes 6 metres, another reads the drawing differently again. Before anybody has selected a product, you're already comparing different scopes.

Automatic or manual: a £10k question on a single gate

A gate is a simple example. If nobody has confirmed whether it's automatic or manual, that one unresolved detail can easily move the price by £10k on a single gate, depending on which assumption a tenderer makes.

How HVM ambiguity can swing cantilever gate pricing by £60k

These gaps don't stay small. Take a pair of cantilever gates where the drawing doesn't say whether they need to be HVM rated. Some tenderers will price a standard cantilever, others will price a crash-rated one, and the gap between those two products can swing £60k on product supply alone, before installation or foundations are even added. Multiply that across two or three openings and the difference isn't a rounding error. It can materially change the perimeter budget before installation and foundations have even been considered.

The legacy PAS68 bollard problem: when the drawing and the spec contradict each other

We still see legacy PAS68 requirements on project specifications, even though BS ISO 22343 is now the current standard. The standard itself isn't the point in this example; the contradiction is that the drawing shows a metal sleeve, concrete filled, 128mm in diameter, but the specification calls for PAS68, 40mph, 7.5 tonne. A bollard built to those dimensions won't achieve that rating, but nobody has flagged the conflict, so at pricing stage roughly half the tenderers price to the drawing and the other half to the specification. Two different products, submitted under the same line item.

Why five tender prices rarely mean five prices for the same thing

Leave a detail up to interpretation and you stop comparing apples with apples. The client gets five prices back, but the spread tells the real story: five interpretations of the same package, not five prices for the same thing. This matters more than it looks, since the perimeter package is oftenpriced by anywhere from 4 to 25 companies, on a scope that, on a data center, makes up less than 1% of the total build cost.

The biggest problems normally come to a head after the project is awarded and the construction team start getting into the detail. If the wrong thing was priced, the contractor is now working to a budget that was never going to cover the job. That's when corners get cut, not because anyone set out to cut them, but because the number was wrong from the start.

Contradictory information doesn't resolve itself

When a drawing and specification genuinely contradict each other, there's no guarantee you end up with what you actually wanted. If you'relucky, someone raises an RFI and you get the chance to say what you meant. If you're not, something else gets priced and carried straight into the technical submittal, timed to get the product on site when it's needed. If that product then fails to meet the actual requirement, and a different security rating is called for, you're not just reordering. You're facing a fresh lead time that was never built into the construction programme.

When ambiguity survives to site

That's before anything goes wrong on site. We've seen fencing scrapped after installation for not meeting spec, for being the wrong height, and, in one case, because it arrived grey when the requirement was black.. At that point it's no longer a pricing problem. Someone is paying to do the work twice.

The hassle cost

There's a cost no schedule of rates captures: the time lost when the same query keeps coming back up the chain. An RFI gets raised, goes to the design team, comes back with a partial answer, gets looked into again. Each cycle eats into a programme that rarely had much slack to begin with, and the client can usually see it happening, which doesn't help confidence in the package.

It also leaves main contractors exposed later than they'd like. A piece of scope that was never clearly resolved can turn up as something simply left out of the price, well after the number's been agreed. And when a drawing and specification genuinely disagree, nobody in the chain can say with confidence which one was supposed to win.

Most of this is still fixable before tender, while an RFI can correct a drawing or specification rather than force a redesign. Once it's built, the only option left is the expensive one.

Security shouldn't be a matter of interpretation

None of this should be left to whoever happens to be pricing the job that week. A perimeter measure is either right for the site or it isn't, and that'snot a call for a tenderer to make. A tenderer's job is to price the information they've been given. It shouldn't be their job to reverse-engineer the client's security strategy. It should be clearly defined: selected for its suitability to the risk profile and the site layout, not just for meeting a rating on paper. Ambiguity isn't a neutral gap that gets filled in fairly. It's a decision made by default, by someone who may not know the threat, the risk or the client's original intent… and whose commercial obligation is to price the tender information in front of them in a cost-effective way to win the project.

How Relkron approaches perimeter risk: the Perimeter Assurance Chain

The reason we look at perimeter security as a chain is that none of these decisions sits in isolation.

THREAT → STRATEGY → STANDARDS → DESIGN → PRODUCT → PROCUREMENT → INSTALLATION → PERFORMANCE

The handovers are where the gaps often appear.

When the client intends X, but the drawings, specification or tender scope describe Y, the market will quite reasonably price Y. That is the security intent gap. And it's far cheaper to find before procurement.

Relkron's Perimeter Design Risk Review is designed to find these gaps before tender: checking whether the drawings, specification, standardsand procurement information still describe the security outcome the client actually intends to buy.

If a perimeter package is approaching tender, that's the point at which correcting an ambiguity is still relatively cheap.

About me

Adam Savage is the founder of Relkron, bringing over 26 years of dedicated, hands-on expertise in the physical perimeter security industry. Throughout his career, Adam has specialised in high-security fencing and gates, hostile vehicle mitigation (HVM), product manufacturing, specification, and navigating complex LPS 1175 standards across international markets.

Having delivered intricate perimeter security systems in over 40 countries, Adam has worked closely alongside clients, consultants, contractors, and manufacturers worldwide.