a. In any case where an applicant for a permit to construct, reconstruct, alter or demolish any improvement on a landmark site, or in an historic district or containing an interior landmark, files such application with the commission together with a request for a certificate of appropriateness, and in any case where a certificate of no effect on protected architectural features is denied and the applicant thereafter, pursuant to the provisions of section 25-306 of this chapter, files a request for a certificate of appropriateness, the commission shall determine whether the proposed work would be appropriate for and consistent with the effectuation of the purposes of this chapter. If the commission's determination is in the affirmative on such question, it shall grant a certificate of appropriateness, and if the commission's determination is in the negative, it shall deny the applicant's request, except as otherwise provided in section 25-309 of this chapter.
b. (1) In making such determination with respect to any such application for a permit to construct, reconstruct, alter or demolish an improvement in an historic district, the commission shall consider (a) the effect of the proposed work in creating, changing, destroying or affecting the exterior architectural features of the improvement upon which such work is to be done, and (b) the relationship between the results of such work and the exterior architectural features of other, neighboring improvements in such district.
(2) In appraising such effects and relationship, the commission shall consider, in addition to any other pertinent matters, the factors of aesthetic, historical and architectural values and significance, architectural style, design, arrangement, texture, material and color.
(3) All determinations of the commission pursuant to this subdivision b shall be made subject to the provisions of section 25-304 of this chapter, and the commission, in making any such determination, shall not apply any regulation, limitation, determination or restriction as to the height and bulk of buildings, the area of yards, courts or other open spaces, density of population, the location of trades and industries, or location of buildings designed for specific uses, other than the regulations, limitations, determinations and restrictions as to such matters prescribed or made by or pursuant to applicable provisions of law, exclusive of this chapter; provided, however, that nothing contained in such section 25-304 or in this subdivision b shall be construed as limiting the power of the commission to deny a request for a certificate of appropriateness for demolition or alteration of an improvement in an historic district (whether or not such request also seeks approval, in such certificate, of construction or reconstruction of any improvement), on the ground that such demolition or alteration would be inappropriate for and inconsistent with the effectuation of the purposes of this chapter, with due consideration for the factors hereinabove set forth in this subdivision b.
c. In making the determination referred to in subdivision a of this section with respect to any application for a permit to construct, reconstruct, alter or demolish any improvement on a landmark site, other than a landmark, the commission shall consider (1) the effects of the proposed work in creating, changing, destroying or affecting the exterior architectural features of the improvement upon which such work is to be done, (2) the relationship between such exterior architectural features, together with such effects, and the exterior architectural features of the landmark, and (3) the effects of the results of such work upon the protection, enhancement, perpetuation and use of the landmark on such site. In appraising such effects and relationship, the commission shall consider, in addition to any other pertinent matters, the factors mentioned in paragraph two of subdivision b of this section.
d. In making the determination referred to in subdivision a of this section with respect to an application for a permit to alter, reconstruct or demolish a landmark, the commission shall consider the effects of the proposed work upon the protection, enhancement, perpetuation and use of the exterior architectural features of such landmark which cause it to possess a special character or special historical or aesthetic interest or value.
e. In making the determination referred to in subdivision a of this section with respect to an application for a permit to alter, reconstruct or demolish an improvement containing an interior landmark, the commission shall consider the effects of the proposed work upon the protection, enhancement, perpetuation and use of the interior architectural features of such interior landmark which cause it to possess a special character or special historical or aesthetic interest or value.