i think it is fair to say that a strip built kayak is strong enough to do the job.  and depending on the particular measure of strength...equals or exceeds the typical commercial kayak like the Solstice.   but in some respects, they are also more fragile.

the key difference between a Guillemot or a Okoume stitch-and-glue is that these are 'cored' structures where the Solstice is a solid laminate.   that is why the strip-built, for example, is typically stiffer while being substantially lighter (10+ lbs) than a comparably sized commercial solid laminate boat.

so what we are talking about conceptually, is the difference between corrugated cardboard and a solid/thick piece of cardboard.

without the corrugation, the solid cardboard is going to be heavy to get anything close to the same stiffness.  but a thick, solid piece of cardboard is strong in its own way.  try to cut a solid piece of carboard or attack it with a knife...it will hold up significantly better than a piece of corrugated cardboard.  

so if its a knife-fight you are concerned about....i would want the solstice.   but if it stiff and lightweight and nothing crazy happening....i would prefer the guillemot.

anyway...its a great question...and a complex topic.  i hope what i have put here helps.

h

i thought i would add a couple more notes (as i am taking a break from my strip-built petrel (designed to come in at 30 lbs).

so the essence of what i am saying above is that before we even get to the topic of commercial vs home built, the primary issue is really about what is the construction technique.  in this case, a cored structure vs a solid laminate.  

you can buy a commercial cored boat....they tend to be quite expensive and reserved to racing boats becuase they don't lend themselves well to high-volume/low cost production the way a solid laminate does.

and a commercial cored boat would also be considered 'not as strong' or 'stronger' in the same way that i described above.

so commercial or home built is typically not what determines 'strength'....the construction technique does.

if we accept that, then, is there something a commercial builder can do that leads to stronger boats given the same construction type than the skilled home-builder?  my short answer is 'no'....that said, there are tools and investments commercial builders make that can have an impact on strength that are not typically used by anything less than the most enterprising home builders.

the most notable investment in this regard would be in vacume bagging technology (which by the way....current design solstice uses).   you can look this up....but most homebuilders would not use this technology.   its expensive and complicated.    that said, the technology is much more important in a solid laminate construction.  but since most homebuilders aren't building solid laminate boats....its not really that big a deal.   and vacume bagging a strip built boat, while impressive, does not make it that much better/stronger boat than not using the technology.

so if i had to have a solid laminate boat....i would be hesitant to buy one that did not use vacume bagging weather commercially built or home built.

so what i am saying in the end is that your homebuilt guillemot is the 'strength' equal of any commercially-built-cored boat using the same glass (e glass, s glass, carbor fibre or kevlar)....

h

As Hspira said it is a case of "apples and oranges"............

A strip built kayak built commercially is just as good as a hobbist built boat given the skill, attention, materials and tools of the builders is equal.  A strip built wood/glass composite is different  than a solid built fiberglass boat and so forth.   

 Define "relative strength"  what strength are we talking about. Is it resistance to puncture?...... bending stresses?  Is it weight?  Is it water tightness? As with my power boats both types of kayaks  can take rough water better than I can....But big waves and/or flood waters will crush them both against rocks, seawalls, etc........... Will it resist an partially restrained flight off the truck at 70 mph?  Recommend a roto molded plastic boat for that.......How strong does it have to be?

I can tell you this much. Oysters will cut the crap out of the hull of a wood composite, fancy carbon fiber composite boat, and/or my feet. Oysters will cut the hull of a solid fiberglass boat but you have to go real deep before it is a problem that needs core penetration remediation. (IE you donn't want wet wood inside the glass)  I can fix the strip boat but gell coat matching so far eludes me. To me constructability is a strength.

 I can tell you that my wife's Valley Etain  is a fine boat, but my C 17 goes everywhere she does and more with less weight and its prettier. (than the Etain)  After the paddle it is a lot lighter to lift up on the top of the truck rack too. That is a strength when my "strength" is waining.

���Thanks Hspira and Sun! That is great information. It sounds like the cored construction is stiffer yet not as impact resistant ( as in hitting a rock) than solid fiberglass. I appreciate your feedback. Bob