Iron Heart is known for its heavyweight, rugged products inspired by motorcycling culture, Americana, and its army of devoted fans. And one of the pillars of Iron Heart’s heavy-duty offering is its Ultra Heavy Flannel (UHF) shirting.
I’ve wanted to take a closer look at this seminal fabric for a while, now, and Iron Heart was nice enough to send us one of their Ultra Heavy Flannel Work Shirts for review. I’m aware that many of you will be aware of this fabric already, and perhaps even own a few UHF pieces yourselves. But for those who don’t and perhaps don’t live near an Iron Heart stockist, I hope that this review helps you decide whether or not investing in some Ultra Heavy Flannel is the right decision for you.
Spoiler alert: it probably is.
By the Numbers
- Name: Iron Heart Ultra Heavy Weight Flannel Workshirt
- Materials: 12oz. 100% Aspero cotton overdyed flannel
- Made in: Japan
- Fit: Runs small, we recommend sizing up
- Details:
- Two button-closure breast pockets, left with pen insert sleeve
- Soft brushed interior
- Reviewed in Overdyed Black but available in a variety of colors and fits
- Available for $360 at Iron Heart
Fabric
Iron Hearts UHF shirts are all about the fabric. It’s in the name! And honestly, I can see why stuff like this gets people hooked on the brand.
Right out of the bag, you can feel that this isn’t your normal flannel. It’s the result of hard work and a commitment to creating a super heavyweight, rugged, and hard-wearing cloth that will be hard to beat. It’s thick but not overbearing, soft on your skin, conforms to your body, and looks incredible.
Ultra Heavy Flannel weighs in at 12 oz. per square yard. It’s woven in Japan using 100% Aspero cotton from the foothills of the Andes mountain range. After weaving and dyeing Iron Heart brushes the inside of the flannel for a super-soft skin feel, and single brushes the face of the fabric for texture. Honestly, 12 oz. flannel shouldn’t be this comfy, but it is. The heft and weave of UHF also make it warm and windproof, which is something that came in handy for me, living in a British coastal area.
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If you want a heavy, robust flannel shirt – this is the end tier. If you want a drapey, lightweight flannel – you should probably steer clear. Maybe Iron Heart should use that as a strapline? But in all seriousness, this is a fabric for those who like their garb on the rugged side.
Speaking of drape, though, UHF still drapes nicely. I’ll explore this in the next section.
Key Facts:
- End-tier 12 oz. Japanese flannel made from Aspero cotton.
- Won’t disappoint if you want a heavyweight flannel shirt.
- Hefty yet comfortable thanks to soft double-brushed inner.
- Warm and windproof.
Fit, Sizing, & Aesthetic
The fit of UHF depends on whether you invest in Iron Heart’s Work Shirt or Western Shirt silhouettes. Each UHF release is available across these silhouettes. I went for the Work Shirt, which is slightly boxier than the Western, with wider shoulders and wider cuff opening. For this reason, I can only comment on the fit of the Work Shirt, but the measurements between the Work and Western aren’t worlds apart.
Iron Heart UHF shirts fit small. Using the size chart, I had to go for a XXL to achieve a slightly loose, casual fit. Note that my shirt fit even smaller than most UHF Shirts as the overdyeing process had removed all shrinkage, but shrinkage is something you always want to consider, especially if you like to wash on the warmer side or use a tumble dryer. I’m usually an L in Western brands and an XL in Japanese brands, so it’s fair to say that Iron Heart runs on the Japanese side of things. Use the size charts provided by IH, size up 1 or 2 and you’ll be good.
In terms of cut, Ultra Heavy Flannel Shirts sit between shirt and overshirt. They’re just roomy enough to layer over a fine knit or sweatshirt, and the fabric isn’t so thick that you can’t just rock it over a t-shirt. Me? I like to rock this over a hefty long-sleeved t-shirt or a lightweight sweatshirt. Whilst UHF is heavy, I wouldn’t be rushing to treat it like a Melton wool overshirt or something — it’s just not cut to be a pure overshirt. And that’s a good thing.
When I felt the heft of UHF, I thought it might be a bit too rigid for my style, but I was pleasantly surprised by how it draped. I’ve had heavyweight twill shirts before which sit kinda awkwardly until they’re broken in. That isn’t an issue, here, although the fabric did break in even further, which I’ll touch on later.
Key facts:
- Iron Heart Ultra Heavy Flannel Shirts fit small – size up and check the measurement charts.
- The silhouette is slim-to-regular fitting depending on how you size.
- The shirt used in this review is pre-shrunk due to overdyeing process.
- Roomy enough to be layered over a sweatshirt or fine knit, but not so heavy that it can only be treated as an overshirt.
Details & Construction
Iron Heart Ultra Heavy Flannel Shirts let the fabric do the talking, which is good because they come in a wide range of plaids. My specific plaid is Overdyed Black. Iron Heart dropped a collection of Overdyed UHF Shirts where they revitalized old excess stock by overdyeing it black using sulfur. As well as creating a unique and understated shirt, this gives the shirt more fading potential.
Submerging the fully constructed shirt in black dye darkens and subdues the lively designs, creating a subtler variation without losing the essence of the original color palette. Being a sulfur dye, the charred appearance will gradually lighten and patinate as the fabric ages, revealing more of the vibrant colors concealed within the weave. – Iron Heart
Iron Heart Overdyed Black Flannel Shirts, available for $360 from Iron Heart.
No matter what plaid or colorway you choose on an Ultra Heavy Flannel, each Shirt comes with a branded woven neck and pocket labels. I particularly like the catseye buttons and pen slot on the Work Shirt. The construction is clean, robust, and full of expertise. Despite the heft of the fabric, nothing is bulky and everything sits nice and flush to the main body of the shirt. You’ve got single, double, and triple needle stitching, and fully felled internal seams. Chain stitch run-off at the hem is always a good look, and the twill taping on the opening above the cuff (pictured below) is a testament to just how well-engineered these shirts are.
Key Facts:
- Clean robust construction featuring single, double, and triple needle stitching.
- Minimal details, letting the fabric do the talking
Patina Potential
As mentioned above, my Ultra Heavy Flannel Shirt is overdyed, meaning it has even more patina potential than other UHF Shirts. My friend, Layton, was kind enough to supply images of how one of his Ultra Heavy Flannels faded over 10 years:
Fades on an Iron Heart Ultra-Heavy Flannel IHSH-87 Shirt after over 10 years of wear. Left image via Max Power on the Iron Heart Forum, right image from Spitfire Dealer on the Iron Heart Forum.
Iron Heart Ultra Heavy Flannel Ombré Check Work Shirt Red/Black, available for $350 from Iron Heart.
Conclusion
It’s not hard to see why Iron Heart’s Ultra-Heavy Flannel Shirts are so popular. To be honest, I’ve found it hard to find a bone to pick with mine. The fit could be boxier for some tastes but that’s not what Iron Heart is aiming for, and sizing up 2 as I did gives you a looser fit, if that’s your thing.
Iron Heart Ultra Heavy Flannel Shirts, available from $350 at Iron Heart.
UHF Shirts come at a cost, but if the construction, Layton’s shirt, and sheer quality of the fabrics are anything to go by, these things last for years with a cost-per-wear profile to be reckoned with. My conclusion is that Iron Heart Ultra Heavy Flannel Shirts are the kind of garment we’re proud to champion at Heddels.
Shop the full Ultra Heavy Flannel collection over at Iron Heart.
