Author: Matthew Cornell

If structural engineers designed buildings the way other engineers approach their fields, the world would be an absolute disaster! 🌍🔥 Let’s take a look at what would happen if we applied their “design principles” to structures:

🔹 Civil Engineering → Your house would be perfectly functional—until a storm hits ⛈️💦… then your lounge room would turn into a swimming pool. 🏊‍♂️

🔹 Mechanical Engineering → Your house would need a service every 10,000 hours 🔧, and you’d have to replace the main beams, trusses, and slabs annually. Forget to service it? Warranty void. Sorry, mate. 🚧😬

🔹 Electrical Engineering → Your house would be standing most of the time… until every few weeks when the walls flicker in and out ⚡🙃. You’ll need to reset the main support beams—in the dark, with a torch. 🔦

🔹 Chemical Engineering → Your house would be built from experimental materials 🧪✨, looking fantastic—until it gets too humid and suddenly dissolves into an exciting (but inconvenient) pink foam. Bonus: it may or may not be toxic. ☣️🤷‍♂️

🔹 Aerospace Engineering → Incredibly lightweight and efficient! 🚀🏠 … But a strong wind might send it straight into your neighbour’s yard. Hope they don’t mind. 🌬️😂 Oh, and you’d need a three-person ground crew with boarding stairs to get out. 🛫

🔹 Environmental Engineering → Your home would be 100% sustainable, organic, and carbon-neutral 🌱🏡… and also decompose into mulch within five years because that’s better for the planet. 🌍♻️

🔹 Biomedical Engineering → Your house would be an architectural marvel, adapting to your needs 🏠💡… but it would cost $2 million, take 20 years of research, and still have a 40% chance of being rejected by the foundation. 🚑😂

🔹 Industrial Engineering → Your home would have an amazingly efficient layout! ⚙️ … Except to get to the kitchen, you’d have to pass through the bathroom twice. 🚪🚻🚶‍♂️

🔹 Software Engineering → Your house would be released in beta with missing walls and regular “patch updates” 🔄🛠️ to fix things like doors that don’t exist and porcelain windows. Eventually, they’d abandon your version and release House 2.0—which is somehow worse, but at least the update is free. 💻🏠🤦‍♂️

🔹 Mining Engineering → Your house would be structurally sound… until someone decided to extract the valuable materials from your support columns. ⛏️💎 Then, well… collapse time! ⏳💥

🔹 Traffic Engineering 🚦→ Some rooms would be One Way ➡️, the walls would buckle under the roof’s weight every morning between 7 AM and 9 AM 😵, and your driveway would be Closed for Maintenance with a 10-person stop-go crew every sixth week. 🚧🚗

Thank goodness structural engineers actually design things to stay up! 🙌🏗️ Otherwise, we’d all be living in glitchy, biodegradable, self-dissolving, wind-propelled nightmares. 😅🏡💨

StructuralEngineering 🏗️ #EngineeringHumour 😂 #CivilEngineering #MechanicalEngineering #ElectricalEngineering #ChemicalEngineering #AerospaceEngineering ✈️ #EnvironmentalEngineering 🌱 #BiomedicalEngineering #IndustrialEngineering #SoftwareEngineering 💻 #MiningEngineering ⛏️ #TrafficEngineering 🚦 #FunnyEngineering #EngineerLife #ConstructionFails 🚧 #BuiltToLast #WhatCouldGoWrong 🤦‍♂️ #ArchitectureJokes #EngineeringMemes #GlitchyHouses #BetaTestingYourHome

Hey #Brisbane
We’re battening hatches in readiness for the storm.
Other engineers are moving their paperwork into their yard so they can claim it was storm damaged and they can’t find the document you need.

So we’ll continue to keep you updated as #Alfred gets closer to the coast. In the meantime, we’re tidying up around home and office, stockpiling some water and cancelling inspections for this Thursday and Friday.

We’ll be available next week if the wind or rain gets too much for you or your home – but generally insurance claims and makesafe teams/builders will be your first priority if your old roof decides not to hang around.

I’ll have more to say in the coming days – but for now – try not to panic buy…. at least until my team has bought some toilet paper and bread….

Nail plate back out.
This is what it looks like.
This is a photo of an older truss. When the truss was installed this steel nail plate was tight in the timber. There was no gap. The teeth of the nailplate were firmly embedded in the timber.
Over time, with changes in the amount of moisture in this roof, the timber pushed and pulled and the steel teeth of the nail plate worked their way out of the timber.
This nailplate is critical in transferring loads and keeping the truss strong. If the teeth aren’t embedded in the timber, the truss is at risk of sagging or worse still pulling apart under wind load.
If your older roof trusses look like they have sagged, this is just one thing we look for.
The solution? The teeth need to be re-engaged in the timber, the loads need to transfer between the pieces of timber again and something needs to be done to ensure the nail plate doesn’t come loose again.
Send a builder or building and pest inspector into your roof to start with.

If you need advice on how to repair this problem, we’re just a phone call away.

Sometimes we recommend replacing the truss. Sometimes we recommend sistering a truss next to the degraded truss. Sometimes, we have bene able to repair the truss in place. It all depends on how many trusses are suffering or are likely to suffer.

For extra credits, have a read of this technical report:
https://fwpa.com.au/wp-content/uploads/2009/04/PNB036-0607_0.pdf

Matt Cornell
Cornell Engineers

If you’re building a sleeper retaining wall, you’ve probably been told you need an ag pipe and drainage system behind it.

But here’s the truth: sleeper walls are already free-draining—water comes straight through the gaps between the sleepers!

So, do you really need all that extra drainage work? Let’s break it down.

How Water Moves Through a Sleeper Retaining Wall

• Sleeper retaining walls are not waterproof. They’re built with gaps between the sleepers, so water flows through naturally.
• When it rains, water seeps through the wall and drains away without needing pipes or fancy systems.
• Unlike solid concrete or block walls, sleeper walls don’t trap water behind them, so hydrostatic pressure (the force of water pushing on the wall) isn’t a big issue.

The Real Job of Gravel Backfill

Gravel backfill is crucial—but not for directing water into pipes. Its real purpose?
✅ Stops soil from washing through the wall gaps
✅ Lets water drain freely behind the wall
✅ Reduces pressure on the sleepers and posts

Without gravel, water can pool behind the wall, making the soil heavy and unstable. That’s when walls start leaning or failing.

Why Ag Pipes and Drainage Systems Don’t Work Here

• Ag pipes rarely drain properly. If they sit too high, water just bypasses them. If they sit too low, they clog with silt.
• Connecting to site stormwater is nearly impossible. Unless you have a proper outlet at the right level, pipes just fill with mud and stop working.
• Gravity does the job for you. Water follows the easiest path—straight through the sleepers and into the ground below.

Need a Watertight Wall? A Sleeper Retaining Wall Isn’t the Right Choice.

If you need a wall that doesn’t leak (for example, to keep water out of a basement or protect a neighbouring property), a sleeper retaining wall isn’t the solution.

For a watertight retaining wall, consider:
✔ Reinforced concrete walls with a waterproof membrane and proper drainage behind
✔ Concrete block walls with a sealed render finish and a properly designed subsoil drainage system

Each of these options requires specific waterproofing solutions to ensure water doesn’t get through and build up behind the wall, causing pressure and failure.

The Bottom Line

Sleeper retaining walls are naturally free-draining. Gravel backfill is a must, but ag pipes and complicated drainage systems won’t fix poor design or bad site conditions. If you need a fully sealed, waterproof wall, sleepers aren’t the right choice—consider concrete or concrete masonry retaining walls instead.

Building a retaining wall? Want it to last? Get in touch with Cornell Engineers—we know what works and what’s just a waste of time.

Here’s your Valentine Day’s gift.

Don’t rely on an engineer’s inspection certificate / Form 12 for structural work unless the person who inspected the work was:

a) an engineer

b) attended the site in person

c) took photos to show they were there

d) can provide those photos upon request

Too many times in recent months we’ve identified poor construction practices as identified by a HOMEOWNER even after the “INSPECTOR” approved the construction. The biggest joke in the industry is waiting to meet the inspector on site and when you call them they say they already inspected the work and it passed!!!

Where in the world are we that homeowners are being asked to know more than an engineers’ inspector who inspects 10 to 20 properties per day?

OH, WAIT! Perhaps that’s the problem!!! Nobody can inspect that many properties in a day when considering travel time, reporting time, and meeting with a builder to ensure they understand the defects/requirements.

Whether the industry is booming or dwindling, people (e.g., builders and engineers) are always looking for shortcuts—trying to find cheaper ways to get the job done.

But are they cheaper when homeowners then have to shoulder the burden of identifying structural deficiencies/problems and getting them fixed?

What of the builder who rightly claims the Form 12 is signed by an engineer so the work MUST be compliant?

• Where does that leave the builder?
• Where does that leave the homeowner?
• Where does that leave the certifier?

Can they rely on the Form 12 and pass the responsibility to the engineer who signed the Form 12?

Go back and read our post on the Dog Ate My Homework. That’s the engineer’s get out of jail free. The paperwork doesn’t exist so the engineer can’t possibly be at fault. Right?

So now we have this endless loop of blame game shifters who have all managed to get away with doing a lacklustre job, backed up by incompetence, missing paperwork, cost-cutting and booming profits for work not even done let alone done well.

Does any of this sound possible in a modern economy? Look next door at the house being renovated! Look over the road at the house being built by that builder with the shiny marketing and promises of 6 month construction period!

Check out your local mass construction builder relaxing in his brand-new office, driving his shiny new luxury car and waving a middle finger at consumers.

Yep. Possible maybe even probable.

And this is in a state where we have a consumer watchdog, builder registration process, several builder’s associations (for protection of the builders against the pesky registration process), registration for engineers (including a stinky, decaying complaints process managed by bureaucrats) and consumers who are already fighting tooth and nail to keep some of their weekly salary for their dream home.

Happy Valentine’s Day. Go and buy some roses.

(first published on Cornell Engineers’ Facebook Account)