This entry is to answer a question posted by Allison on Tuesday, June 30, 02009. Her question is as follows:
What do we know about the roof of Anne Hathaway's cottage? It looks like it'd be complicated to build- but does water run off it better?
Allison, I made a cursary attempt to find information on the thatching of Hathaway's cottage in particular, but, alas could not. Luckily, I've done some research on thatching in the past and will bring that to bear in order to answer your question. While thatching varies in the details of technique, material, and tradition from county to county throughout England, generalisations concerning the fundamentals of the technique can, I believe, be made.
Thatch has, I'm told, good-to-excellent run-off properties (more on that below) and is generally built extending a couple of feet past the house line, so gutters aren't necessary. On a different note, it's also regarded as being "green". It keeps houses warm in the winter and cool in the summer and can be produced from locally available materials, although water reeds from China and elsewhere are being used in England (with dubious benefit over more traditional and local straw, water reeds, and wheat reed in roofing effectiveness).
To start off, here are a few more of my pictures of Hathaway's cottage - larger versions are available by clicking.
You'll note the white "caulking" around the chimney. This prevents water from seeking into that juncture and was, traditionally, lime mortar. This was, during the past century, largely supplanted by cement or lead flashing - I'm not sure what the modern material is, but it's likely chosen with an eye for heat containment as well.
Most thatch fires are believed to start as a result of smoldering where the thatch contacts the chimney, or still-burning materials leaving the chimney flu. Sparks from indoors are not considered a major hazard. Further, it's believed that thatch roofs are generally about as combustable as hardwood roofs, or roofs of similar materials. The difference is that the depth of the thatch (often more than a foot) and its effectiveness at shedding water act in concert to produce highly destructive fires.
The netting you see covering the roof is not a structural component, but instead prevents birds from picking holes in the roof. The netting's designed for easy removal during a fire, since the most effective way of saving the house is to remove the thatch, rather than dousing it. Aesthetics for Hathaway's combined with the expense of a Master Thatcher and their relative rarity account for the netting here.
Speaking of which, no regulatory body commissions Thatchers, so the title of Master is self-designated.
The roof is constructed of wood beams, with thinner cross braces unto which the thatch is lashed, hooked, or otherwise affixed in small bundles repeatedly in an overlapping manner till the roof is covered, as depicted below.
Depending on local weather conditions, the skill of the thatcher, and the materials used, fifteen years is the minimum life-span you'd expect from a roof with sixty or more years before rethatching not being unheard of. This is inclusive of patching to the ridgeline, which experiences the heaviest wear, and to places which have incurred other localised damage.
It's common in many places to rethatch by removing and replacing the rotted upper layer, since water penetration typically doesn't extend through the whole depth of the roof. Some under layers date back more than 600 years offering insight into traditional thatching methods, agriculture, fire fuel, and cooking (from sooty ceilings). For this reason, old thatched roofs enjoy a protected status in Britain and it's quite possible that parts of Hathaway's thatching survive from her time.
They say a picture is worth a thousand words, so in addition to the 7,548 words before this one, I'll offer approximately 22,000 more.
Combed Wheat Reed
Windows and chimneys, as you may have noticed, are complicated for thatchers, which is why many upper-story windows are "eyebrowed".
And you have varying approximations of eyebrowing…
…till you finally get away from it - which makes the thatcher unhappy and introduces areas of increased wear.
But it's all a compromise for letting light and sight-lines into the upper-stories of older houses which, increasingly, had their upstairs being used in "non-traditional" ways.
I hope this helps answer your question - if you'd have any more questions, et cetera, do let me know.