1850.] 



THE CIVIL ENGINEER AND ARCHITECT'S JOURNAL. 



221 



Mr. FooGo said that one account stated the master of the works 

 received I3s. per week, which at the present value of money would 

 he 10 guineas a week. The whole cost of Caernarvon Castle was 

 stated to have been 250,000/., but that did not include various 

 expenses, such as carrying the stone from the quarry, which were 

 imposed upon the inhabitants of the neighbourhood. 



Mr. Fowi.EB having suggested that the vote of thanks should 

 include the name of .Mr. Salvin, to whom they were indebted for 

 the drawings hy which the paper was illustrated. 



The CHAiHMiN replied that he had a resolution in his hand to 

 that effect, and expressed a hope that Mr. Salvin would give them 

 a few remarks upim his illus'rations some other evening. 



The vote of thanks was then passed by acclamation. 



CEMENTS AND STUCCO. 



On the Propriety of the Ap/iliratioii nf Cements or other Artijirinlhj- 

 fiirmed Materials to the Exteriors of Buildings. By Jamks 'I'iiomas 

 K.NowLES. — (Paper read at the Royal Institute of British Archi- 

 tects, .May 27, 1950.) 



In submitting the paper which I have now to read, I am in- 

 fluenced by the appeal of the Council to the Members of our 

 Institute for active co-operation; by a desire to assist in re- 

 moving some of those objections which have been often made to a 

 very valuable class of materials; and by the hope of eliciting a 

 discussion which may be to some who are assembled here to-night 

 lioth interesting and instructive. But, befoi-e I enter upon this 

 ditficult and much-vexed question, I wish to state distinctly, that 

 wherever I may express an opinion of my own, unsupjiorted by 

 actual observation, I shall do so with great diffidence, and with 

 the feeling that such opinion may be proved, hereafter, to be 

 erroneous; because I feel that, before the nature of cements or 

 stuccoes can be clearly understood, a larger amount of statistical 

 details, and a much more correct knowledge of the chemical 

 changes which are produced by apparently minute differences in 

 the materials themselves or in the conditions under which they 

 are applied, than is possessed at present, are absolutely necessary. 



As my object, on this occasion, is rather to state the result of 

 my own observation and experience, than to i-epaat what may be 

 gleaned from the works of those who have written upon the 

 subject, I would also ask you to excuse what may appear like 

 egotism in the allusicns which I shall have to make to buildings of 

 my own. and to believe that I adopt this course simplv because it 

 is impossible for me to speak, with the same degree of certainty, 

 of works with which I am less intimately acquainted. 



Although the practice of covering the exteriors of buildings 

 with some description of plastic materials appears to have pre- 

 vailed from a very early period, it will, I think, be readily ad- 

 mitted, that in our own age and country this practice has been 

 carried beyond all former precedents. It would be quite impossi- 

 ble, on an occasion like the present, to enumerate all the causes 

 which have produced, or have assisted in producing, this result; 

 but. perhaps, as among the most prominent of these, I may men- 

 tion the cold and humid atmosphere of our northern climate; the 

 impossibility (in many localities) of obtaining, except at a cost 

 too great to be incurred, such materials as will effectually resist 

 the destroying influences of rain and frost; and a growing inclina- 

 tion on the part of our employers to add something of the beau- 

 tiful in form to that convenience of arrangement and fitness for 

 the intended purpose, without which the most elaborate produc- 

 tions of our art are really failures, or can at best be deemed but 

 splendid errors. 



It is true, that, when the practice of employing stuccoes and 

 cements for covering the exteriors of buildings was first adopted, 

 the science of geology had not revealed that valuable page in the 

 great book of nature which has recently attracted so large a 

 measure of study and attention, and that the nature and quality 

 of the materials which compose the crust of our planet are, 

 through the aid of that modern science, better understood by us 

 than they could be by those who were engaged in the art of build- 

 ing before this source of knowledge had been revealed. Yet this 

 additional knowledge upon a subject so deeply interesting to the 

 architect, has tended to confirm the impression which previously 

 existed, by showing him, that in many portions of the united 

 kingdom no building stone can be obtained capable of effectually 

 excluding moisture, or of resisting for any lengthened period 

 the vicissitudes of our climate; and by convincing him, that, in 

 order to secure in such cases, dry, healthful, warm, and comfort- 



able habitations (especially when buildings are rapidly erected, 

 and occupied immediately after their completion), two things are 

 absolutely necessary, and a third is exceedingly desirable: — 



1st. That the outer face of all the external walls should have a 

 covering, or skin, of some material impervious to water. — 2ndly. 

 That the moisture from the earth should be prevented from rising 

 into the brick, or stonework, by the introduction of some water- 

 proof material into iiU tlie external and internal walls and parti- 

 tions immediately above the ground level. — 3rdly. (Where bricks 

 are employed, and a proper amount of careful supervision can be 

 exercised) — that the external walls should be hollow, with an air 

 space of 4, or 4^ inches between the external and internal work, 

 excepting at the jambs of the openings, and the jioints of junction 

 with the internal walls. 



That the necessity for these, or similar precautions, in the erec- 

 tion of dwelling houses in exposed situations, is perfectly well 

 known to the elder members of the profession, and that they 

 adopt them in their practice, I entertain no doubt; but as tlieir 

 advantages may not be equally clear to tliose who have yet to 

 enter upon the practical department of our art, and lest they 

 should imagine that I am speaking theoretically, and not from 

 actual experience, I will mention — That the house, of which one 

 of the elevations is now exhibited, was erected about six years 

 ago, in an exposed situation, and on a stiff clay soil; that the 

 carcass was carried up in an unusually wet autumn, and the walls 

 exposed to heavy and continuous rains; that no wall battening 

 was used in any portion of the building, which was roofed-in at 

 the end of December, and completed and inhabited by the end of 

 the following October, at which period it was quite fit for occupa- 

 tion; that there has never been since that time the slightest 

 appearance of damp in any portion of it, from the basement to the 

 roof, nor is the smallest settlement perceivable; and this result is, 

 I believe, mainly, if not entirely, attributable to the adoption of 

 those precautions which I have mentioned as being, in my opinion, 

 essential in nearly all cases, and to one other, which is only 

 important on clay soils — that is, the covering of the whole area 

 occupied by the building with a bed of concrete, which should not 

 be less than six, and need not be more than twelve, inches in 

 thickness. 



To those who have been accustomed to build only in London, or 

 in other towns and cities, it would, I believe, be quite impossible 

 to convey an adequate idea of the difficulties which must fre- 

 quently be encountered by those to whom the erection of isolated 

 houses in very exposed situations is intrusted; when (as very fre- 

 quently happens) no such stone or bricks can be obtained as will 

 effectually resist the rain, and pi-event it, when accompanied by 

 heavy gales of wind, from passing through the walls. 



I could, if time permitted, mention many remarkable instances 

 of the mechanical force with which the rain is sometimes driven 

 horizontally against the walls of buildings in elevated positions; 

 but I will select one only, which made a great impression on my 

 mind. During a visit to a large building in course of erection on 

 Black Down (the highest ground, I believe, in North Devon), I 

 observed a portion of a nine-inch partition wall saturated with 

 water. As the building had been roofed-in some weeks before, I 

 was a good deal surprised at this appearance; but I had an oppor- 

 tunity a few days afterwards of witnessing what explained to me 

 the cause of it'; for, being on the spot during a heavy gale of 

 wind and rain, I stood for some time watching the result, and saw 

 the rain passing through a window opening across eighteen feet of 

 space, and striking with great force against the opposite internal 

 wall, and in the course of about an hour making its appearance on 

 the other side. 



Very shortly after witnessing this occurrence, I was called upon 

 to examine a church, which had been erected in a similarly ex- 

 posed position, through the walls of %vliich (even those of the 

 tower), the rain found admission to the interior in very large 

 quantities. Three or four years having been suffered to elapse, 

 during which this evil was found to be continually increasing, the 

 walls were covered with stucco, of the kind which I shall have 

 hereafter to describe, which proved in that, as it has done in all 

 other cases with which I am acquainted, perfectly effective. 



Contenting myself with the remark, that in no single instance 

 have I known the external application of a well-made and care- 

 fully-used stucco, to fail in accomplishing the desired object, I 

 will proceed to combat those which appear to me to be the 

 strongest of the objections which are advanced against this mode 

 of protecting and adorning the exteriors of our buildings, viz. — 



That cements and stuccoes are not durable, and require frequent 

 and expensive reparations. 



